This paper explores the history of the biomedical construction of women's bodies as social bodies in the formation of colonial modernity in Korea. To do so, I engage with Michel Foucault's concepts of governmentality and biopolitics and the postcolonial history of medicine that has critically revisited these Foucauldian notions. These offer critical insights into the modern calculation of population and the biomedical gaze on female bodies on the Korean Peninsula under Japan's colonial rule (1910-1945). Foucauldian reflections on governmentality and colonial medicine can also shed light on the role of biomedical physicians in the advancement of colonial biopolitics. Biomedical physicians-state and non-state employees This paper explores the history of the biomedical construction of women's bodies as social bodies in the formation of colonial modernity in Korea. To do so, I engage with Michel Foucault's concepts of governmentality and biopolitics and the postcolonial history of medicine that has critically revisited these Foucauldian notions. These offer critical insights into the modern calculation of population and the biomedical gaze on female bodies on the Korean Peninsula under Japan's colonial rule (1910-1945). Foucauldian reflections on governmentality and colonial medicine can also shed light on the role of biomedical physicians in the advancement of colonial biopolitics. Biomedical physicians-state and non-state employees and colonizers and colonized alike - served as key agents investigating, knowing, and managing, as well as proliferating a discourse about, women's bodies and reproduction during Japan's empire-building. In particular, this paper sheds light on the processes by which Korean women's bodies became the objects of intense scrutiny as part of an attempt to quantify, as well as maximize, the total population in late colonial Korea. In the aftermath of the establishment of the Manchurian puppet state in 1932, Japanese imperial and colonial states actively sought to mobilize Koreans as crucial human resources for the further penetration of Japan's imperial holdings into the Chinese continent. State and non-state medical doctors meticulously interrogated, recorded, and circulated knowledge about the sexual and conjugal practices and reproductive life of Korean women in the agricultural sector, for the purposes of measuring and increasing the size, health, and vitality of the colonial population. At the heart of such medical endeavors stood the Investigative Committee for Social Hygiene in Rural Korea and Japan-trained Korean medical students/physicians, including Chóe Ŭg-sŏk, who carried out a social hygiene study in the mid-1930s. Their study illuminates the ways in which Korean women's bodies entered the modern domain of scientific knowledge at the intersection of Japan's imperialism, colonial governmentality, and biomedicine. A critical case study of the Investigative Committee's study and Chóe can set the stage for clarifying the vestiges as well as the reformulation of knowledge, ideas, institutions, and activities of colonial biopolitics in the divided Koreas.