Using data on the characteristics of 1,043 physicians graduated from a medical school in Korea, we analyze the effects of immigrant status, gender, and year of graduation on their choice of medical practice specialty. The specialty areas are categorized into two groups, “core” and “periphery”, on the basis of the reported median income of practitioners in each specialty. The results of our log-linear model analyses indicate that female physicians were more likely to immigrate to the United States than male physicians, although the general trend of immigration did not notably change over time. In our main equation, immigrant status shows a significant peripherization effect as immigrant physicians were much more likely to practice in peripheral areas than their home-staying counterparts. Gender status is also found to have a significant peripherization effect. When these Korean immigrant physicians are compared with the U.S.-educated physicians in regard to their areas of practice, the same pattern of peripherization is observed among the immigrants. Our findings suggest that, despite their secular image of “success”, immigrant professionals in the United States carry on the same kind of marginal economic activities within the professional labor market as unskilled immigrant workers do within the nonprofessional labor market.