The purpose of this study is to analyze the relative efficiency of overseas Korean schools receiving financial support under the Act on Educational Support for Korean Nationals Abroad. The investigation includes identifying environmental factors that influence efficiency. To achieve this goal, data envelopment analysis (DEA), a method suitable for measuring efficiency, was employed to assess overseas Korean schools. The analysis covered a three-year period from 2020 to 2022, comparing and scrutinizing the efficiency of these schools during this timeframe. In addition, the study utilized the Tobit model to examine the impact of various factors on the efficiency of overseas Korean schools. These factors include the country of the school's location, educational objectives, student size, school system organization, ownership of land and buildings, school corporation, development fund, years of establishment, and the GDP of the host country. The Tobit model was employed to analyze how these variables influence the efficiency of the schools. As a result of the empirical analysis conducted from 2020 to 2022, the relative efficiency of overseas Korean schools was measured. The study identified 9 schools exhibiting Constant Return to Scale(CRS) and distinguished 25 schools with either Decreasing Return to Scale(DRS) or Increasing Return to Scale(IRS). The impact on efficiency indicates that schools located in Northeast Asia and large-scale schools demonstrated relatively high efficiency. Contrary to expectations, school corporation and completed school system organization exhibited relatively lower efficiency. Lastly, the lower the GDP of the host country, the higher the efficiency. This study identified inefficiencies in terms of technology and scale of overseas Korean schools. By analyzing environmental factors, information on the direction of government financial support can be provided. It is expected that this evaluation of the efficiency of overseas Korean schools will serve as basis for establishing strategies to strengthen the effectiveness of government subsidies.