Objectives This study aims to analyze the domestic research trends in the study of the declining school-age population due to the low birthrate, currently the million-dollar question in Korea. Based on the results, the study will provide meaningful basic data for the conception and establishment of education policies and suggest efficient research directions for subsequent studies to help strengthen educational competitiveness that determines the country's future.
 Methods To this end, 62 studies were selected after searching and classifying 110 domestically published dissertations and academic journal articles from 2000 to August 2022, and the research trends were analyzed in terms of the research period, research subjects, research regions, and research topics through classification analysis criteria and inter-rater agreement verification. The research tool used for descriptive statistics was Excel to calculate frequencies and percentages. 
 Results Major results are as follows: First, there were 5 (8.1%) research papers on school consolidation, closure, and relocation, which were classified as hardware, as a research topic, which accounted for the highest number, followed by 4 (6.5%) research papers on how to utilize idle and spare classrooms, and 9 (50%) research papers related to these two keywords. In the research keywords categorized as software, there was a slight difference in ranking by topic, and among them, research papers with keywords related to the development and improvement directions of education, future-oriented education, etc. accounted for the largest number of 6 (9.7%), followed by research papers on student placement planning with 5 (8.1%). Second, in terms of yearly trends, from 2000 to 2013, there were 0-1 studies, and from 2015 onward, there were 3-5 studies published annually, with a significant increase in 2020, when the urgency of the declining school-age population hit the ground running. Third, in terms of human aspects, the biggest number of 30 papers (47.6%) studied teachers, students, and parents as research subjects, and in terms of physical aspects, the biggest number of 26 papers (41.3%) studied schools and facilities. Fourth, in terms of the distribution of regions studied, an overwhelming number of 26 papers (41.9%) focused on the national level, followed by 8 papers (12.9%) focused on the capital area, including Seoul. There were 1-2 research papers for each metropolitan city, but none of them studied Gwangju Metropolitan City. Of the 75 autonomous cities in Korea, only 12 cities (16%), including the first-phase new towns, were studied under the keyword of “declining school-age population,” and of the 8 provincial regions, only 3 regions, Chungcheongnam-do, Chungcheongbuk-do, and Gyeongsangnam-do, were not studied and compared.
 Conclusions Based on the derived results, we summarized the tendencies of research trends for papers related to the declining school-age population and suggested implications for further studies in terms of diversifying and deepening research and its necessity.