In South Korea, approximately 70.69 percent of the population was between 15 and 64 years old in 2023, while those above the age of 64 made up around 18.34 percent. The youngest generation made up an even smaller percentage than the elderly, but were the only group that did not increase in size over the last decade, partly due to a decrease in births since 2007. Reasons for fewer children While it is not always the case that family sizes shrink when there are less births per woman, the fertility rate in South Korea is undisputably decreasing overall and less children are born. The reasons people cite for having fewer children vary greatly by gender and marital status in South Korea: For example, more married people than singles - and of those more married women than men - say that the difficulty of maintaining a work life balance is the largest concern for them. Meanwhile, men express more economic concerns about child support, and notably more singles nowadays say they feel no need to have children.

In 2025, the total population of South Korea is projected to be around 51.68 million. In thirty years, the number of people aged 15 to 64 is estimated to decrease by one-third, while the number of older adults is anticipated to more than double. Additionally, the overall population is expected to decline by around six million people by that time. Declining birth rate Several factors are contributing to the expected demographic changes in South Korea. Firstly, the birth rate has been declining for years. As of 2024, South Korea had the lowest fertility rate in the world. This trend continues despite the efforts of successive governments to encourage young people to have children. An increasing number of South Korean women are prioritizing their careers, often choosing to focus on work rather than starting a family at a young age. While the employment rate for South Korean women is still lower than that of men, it has steadily risen over the past decade. Increase in life expectancy Secondly, life expectancy in South Korea has steadily increased due to improved living standards and healthcare. The average life expectancy at birth for South Koreans has risen from less than 75 years to almost 83 years over the past twenty years. As a result, the proportion of people aged 65 and older has grown from less than 11 percent to around 18 percent in the last decade.

The statistic shows the total population of South Korea from 2019 to 2023, with projections up until 2029. In 2023, the total population of South Korea was about 51.71 million people. Population of South Korea South Korea, also called Republic of Korea, has one of the highest population densities worldwide, i.e. a very high number of inhabitants per square kilometer. However, this does not equal bad standard of living; on the Human Development Index, which ranks countries by their level of living standards using key factors, such as unemployment rate, literacy rate, fertility and mortality rates, etc., South Korea is among the highest-ranked countries. When looking at the aforementioned key factors, South Korea indeed seems to offer a fairly stable environment for its inhabitants, economically and demographically: The country’s unemployment rate has been relatively steady for the past decade, its gross domestic product (GDP) is constantly increasing, and it is among the countries with the highest trade surplus worldwide. As for standard of living, life expectancy at birth in South Korea is among the highest worldwide – South Korea is even mentioned in a recent ranking of the best birthplaces for children. Despite the high population density, South Korea is now one of the countries with the lowest fertility rates, i.e. the number of babies born by women of childbearing age. This apparent discrepancy could be explained by a high number of immigrants coupled with the aforementioned high life expectancy.

WorldPop produces different types of gridded population count datasets, depending on the methods used and end application. Please make sure you have read our Mapping Populations overview page before choosing and downloading a dataset.

A description of the modelling methods used for age and sex structures can be found in "https://pophealthmetrics.biomedcentral.com/articles/10.1186/1478-7954-11-11" target="_blank"> Tatem et al and Pezzulo et al. Details of the input population count datasets used can be found here, and age/sex structure proportion datasets here.
Both top-down 'unconstrained' and 'constrained' versions of the datasets are available, and the differences between the two methods are outlined here. The datasets represent the outputs from a project focused on construction of consistent 100m resolution population count datasets for all countries of the World structured by male/female and 5-year age classes (plus a <1 year class). These efforts necessarily involved some shortcuts for consistency. The unconstrained datasets are available for each year from 2000 to 2020.
The constrained datasets are only available for 2020 at present, given the time periods represented by the building footprint and built settlement datasets used in the mapping.
Data for earlier dates is available directly from WorldPop.

WorldPop (www.worldpop.org - School of Geography and Environmental Science, University of Southampton; Department of Geography and Geosciences, University of Louisville; Departement de Geographie, Universite de Namur) and Center for International Earth Science Information Network (CIESIN), Columbia University (2018). Global High Resolution Population Denominators Project - Funded by The Bill and Melinda Gates Foundation (OPP1134076). https://dx.doi.org/10.5258/SOTON/WP00646

In 2024, the population of South Korea was estimated to be about 51.75 million. The population of North Korea was approximately 25.87 million, which is roughly half the population of South Korea. Economic comparison between South and North Korea Following the Korean War (1950-1953), South Korea and North Korea pursued vastly different trajectories, not only politically but also economically. South Korea embraced capitalism and free market principles, which fueled its rapid economic growth and transformed it into one of the world's leading economies. In contrast, North Korea adopted a state-controlled, centrally planned economy, leading to isolation and economic stagnation. While South Korea's gross domestic product (GDP) reached around 2,401 trillion South Korean won in 2023, only about 40 trillion won was recorded for North Korea. Food crisis in North Korea North Korea has faced food insecurity for a long time, and this has been exacerbated in the aftermath of the COVID-19 pandemic. It was estimated that the country had a food shortage of around 860,000 metric tons in 2023. Although the North Korean government maintains a centrally planned economic system, food distribution has long been a problem, as an increasing number of North Korean defectors have reported that they have never received food from North Korean authorities.

A core collection is a subset that represents genetic diversity of the total collection. Soybean (Glycine max (L.) Merr.) is one of major food and feed crops. It is the world’s most cultivated annual herbaceous legume. Constructing a core collection for soybean could play a pivotal role in conserving and utilizing its genetic variability for research and breeding programs. To construct and evaluate a Korean soybean core collection, genotypic and phenotypic data as well as population structure, were analyzed. The Korean soybean core collection consisted of 430 accessions selected from 2,872 collections based on Affymetrix Axiom® 180k SoyaSNP array data. The core collection represented 99% of genotypic diversity of the total collection. Analysis of population structure clustered the core collection into five subpopulations. Accessions from South Korea and North Korea were distributed across five subpopulations. Analysis of molecular variance indicated that only 2.01% of genetic variation could be explained by geographic origins while 16.18% of genetic variation was accounted for by subpopulations. Genome-wide association study (GWAS) for days to flowering, flower color, pubescent color, and growth habit confirmed that the core collection had the same genetic diversity for tested traits as the total collection. The Korean soybean core collection was constructed based on genotypic information of the 180k SNP data. Size and phenotypic diversity of the core collection accounted for approximately 14.9% and 18.1% of the total collection, respectively. GWAS of core and total collections successfully confirmed loci associated with tested traits. Consequently, the present study showed that the Korean soybean core collection could provide fundamental and practical material and information for both soybean genetic research and breeding programs.

A genome-wide assessment of genetic diversity and population structure of Korean native cattle breedsPlink format Ped and Map fileData.zip

There are various hypotheses on dog domestication based on archeological and genetic studies. Although many studies have been conducted on the origin of dogs, the existing literature about the ancestry, diversity, and population structure of Korean dogs is sparse. Therefore, this study is focused on the origin, diversity and population structure of Korean dogs. The study sample comprised four major categories, including non-dogs (coyotes and wolves), ancient, modern and Korean dogs. Selected samples were genotyped using an Illumina CanineHD array containing 173,662 single nucleotide polymorphisms. The genome-wide data were filtered using quality control parameters in PLINK 1.9. Only autosomal chromosomes were used for further analysis. The negative off-diagonal variance of the genetic relationship matrix analysis depicted, the variability of samples in each population. FIS (inbreeding rate within a population) values indicated, a low level of inbreeding within populations, and the patterns were in concordance with the results of Nei’s genetic distance analysis. The lowest FST (inbreeding rate between populations) values among Korean and Chinese breeds, using a phylogenetic tree, multi-dimensional scaling, and a TreeMix likelihood tree showed Korean breeds are highly related to Chinese breeds. The Korean breeds possessed a unique and large diversity of admixtures compared with other breeds. The highest and lowest effective population sizes were observed in Korean Jindo Black (485) and Korean Donggyeong White (109), respectively. The historical effective population size of all Korean dogs showed declining trend from the past to present. It is important to take immediate action to protect the Korean dog population while conserving their diversity. Furthermore, this study suggests that Korean dogs have unique diversity and are one of the basal lineages of East Asian dogs, originating from China.

In 2023, about 728,700 people from ASEAN countries were residing in South Korea, an increase from around 651,300 in the previous year. The majority of these ASEAN citizens were temporary residents, followed by those holding work visas.

Summary of all detected SNVs identified from 5 abalone populations.

Raw dataset of eight microsatellite loci for the 16 populations_RametRaw dataset (ramets sampled) of eight microsatellite loci for the 16 populations from Jeju Island and the South Sea in KoreaRaw dataset of eight microsatellite loci for the 16 populations_GenetRaw dataset (genets) of eight microsatellite loci for the 16 populations from Jeju Island and the South Sea in Korea

To determine the origin and genetic consequences of anagenesis in Rubus takesimensis on Ulleung Island, Korea, we compared the genetic diversity and population structure of R. takesimensis with those of its continental progenitor R. crataegifolius. We broadly sampled a total of 315 accessions in 35 populations and sequenced five noncoding regions of chloroplast DNA. Rubus takesimensis emerged as nonmonophyletic and several geographically diverse continental populations were likely responsible for the origin of R. takesimensis; the majority of R. takesimensis accessions were sisters to the clade containing accessions of R. crataegifolius, primarily from the Korean peninsula, while rare accessions from three populations shared common ancestors with the ones from the southern part of the Korean peninsula, Jeju Island, and Japan. A few accessions from the Chusan population originated independently from the Korean peninsula. Of 129 haplotypes, 81 and 48 were found exclusively in R. crataegifolius and R. takesimensis, respectively. We found unusually high genetic diversity in two regions on Ulleung Island and no geographic population structure. For R. crataegifolius, two major haplotype groups were found; one for the northern mainland Korean peninsula, and the other for the southern Korean peninsula and the Japanese archipelago. Compared with populations of R. crataegifolius sampled from Japan, much higher haplotype diversity was found in populations from the Korean peninsula. The patterns of genetic consequences in R. takesimensis need to be verified for other endemic species based on chloroplast DNA and independent nuclear markers to synthesize emerging patterns of anagenetic speciation on Ulleung Island.

In 2023, the largest age group in Seoul, South Korea's capital, was the age group between 25 and 29, with about 800,000. While about one-fifth of South Korea's total population lives in Seoul, the city's population has declined steadily in recent years.

WorldPop produces different types of gridded population count datasets, depending on the methods used and end application. Please make sure you have read our Mapping Populations overview page before choosing and downloading a dataset.

A description of the modelling methods used for age and sex structures can be found in "https://pophealthmetrics.biomedcentral.com/articles/10.1186/1478-7954-11-11" target="_blank"> Tatem et al and Pezzulo et al. Details of the input population count datasets used can be found here, and age/sex structure proportion datasets here.
Both top-down 'unconstrained' and 'constrained' versions of the datasets are available, and the differences between the two methods are outlined here. The datasets represent the outputs from a project focused on construction of consistent 100m resolution population count datasets for all countries of the World structured by male/female and 5-year age classes (plus a <1 year class). These efforts necessarily involved some shortcuts for consistency. The unconstrained datasets are available for each year from 2000 to 2020.
The constrained datasets are only available for 2020 at present, given the time periods represented by the building footprint and built settlement datasets used in the mapping.
Data for earlier dates is available directly from WorldPop.

WorldPop (www.worldpop.org - School of Geography and Environmental Science, University of Southampton; Department of Geography and Geosciences, University of Louisville; Departement de Geographie, Universite de Namur) and Center for International Earth Science Information Network (CIESIN), Columbia University (2018). Global High Resolution Population Denominators Project - Funded by The Bill and Melinda Gates Foundation (OPP1134076). https://dx.doi.org/10.5258/SOTON/WP00646

The routine collection and use of genomic data are useful for effectively managing breeding programs for endangered populations. Linkage disequilibrium (LD) using high-density DNA markers has been widely used to determine population structures and predict the genomic regions that are associated with economic traits in beef cattle. The extent of LD also provides information about historical events, including past effective population size (Ne), and it allows inferences on the genetic diversity of breeds. The objective of this study was to estimate the LD and Ne in three Korean cattle breeds that are genetically similar but have different coat colors (Brown, Brindle and Jeju Black Hanwoo). Brindle and Jeju Black are endangered breeds with small populations, whereas Brown Hanwoo is the main breeding population in Korea. DNA samples from these cattle breeds were genotyped using the Illumina BovineSNP50 Bead Chip. We examined 13 cattle breeds, including European taurines, African taurines and indicines, and hybrids to compare their LD values. Brown Hanwoo consistently had the lowest mean LD compared to Jeju Black, Brindle and the other 13 cattle breeds (0.13, 0.19, 0.21 and 0.15–0.22 respectively). The high LD values of Brindle and Jeju Black contributed to small Ne values (53 and 60 respectively), which were distinct from that of Brown Hanwoo (531) for 11 generations ago. The differences in LD and Ne for each breed reflect the breeding strategy applied. The Ne for these endangered cattle breeds remain low; thus, effort is needed to bring them back to a sustainable tract.

In 2023, the population aged 65 or older in South Korea made up approximately 19 percent of the total population. The share of older people in the total population has almost tripled in the last two decades.

Constrained estimates of total number of people per grid square broken down by gender and age groupings (including 0-1 and by 5-year up to 90+) for Democratic People's Republic of Korea, version v1. The dataset is available to download in Geotiff format at a resolution of 3 arc (approximately 100m at the equator). The projection is Geographic Coordinate System, WGS84. The units are estimated number of male, female or both in each age group per grid square.

The difference between constrained and unconstrained you can read on this page: https://www.worldpop.org/methods/top_down_constrained_vs_unconstrained

File Descriptions:

{iso} {gender} {age group} {year} {type} {resolution}.tif

iso

Three-letter country code

gender

m = male, f= female, t = both genders

age group

• 00 = age group 0 to 12 months
• 01 = age group 1 to 4 years
• 05 = age group 5 to 9 years
• 90 = age 90 years and over

year

Year that the population represents

type

CN = Constrained , UC= Unconstrained

resolution

Resolution of the data e.q. 100m = 3 arc (approximately 100m at the equator)

Human assisted movement has allowed the Asian longhorned beetle (ALB, Anoplophora glabripennis (Motschulsky)) to spread beyond its native range and become a globally regulated invasive pest. Within its native range of China and the Korean peninsula, human-mediated dispersal has also caused cryptic translocation of insects, resulting in population structure complexity. Previous studies used genetic methods to detangle this complexity but were unable to clearly delimit native populations which is needed to develop downstream biosurveillance tools. We used genome-wide markers to define historical population structure in native ALB populations and contemporary movement between regions. We used genotyping-by-sequencing to generate 6,102 single nucleotide polymorphisms (SNPs) and amplicon sequencing to genotype 53 microsatellites. In total, we genotyped 712 individuals from ALB's native distribution. We observed six distinct population clusters among native ALB populations, with a clear delineation between northern and southern groups. Most of the individuals from South Korea were distinct from populations in China. Our results also indicate historical divergence among populations and suggest limited large-scale admixture, but we did identify a restricted number of cases of contemporary movement between regions. We identified SNPs under selection and describe a clinal allele frequency pattern in a missense variant associated with glycerol kinase, an important enzyme in the utilization of an insect cryoprotectant. We further demonstrate that small numbers of SNPs can assign individuals to geographic regions with high probability, paving the way for novel ALB biosurveillance tools.

The most significant f3 statistics shown the possible ancestor mixture of Korean, ancient dog populations and outgroup.

Pairwise FST (inbreeding between populations) lower diagonal, and Nei’s genetic distance between populations upper diagonal.