For college-educated immigrants, investing in a US postgraduate degree plays a critical role in skill transfer and career enhancement. However, little is known about the role of the US occupational structure, a key aspect in immigrants' context of reception, in shaping immigrants' postgraduate decisions. Using 2015 National Survey of College Graduates and linking three occupational characteristics to the field of study of bachelor's degree from the Survey of Income and Program Participation and Current Population Survey, this article examines the associations of rising educational expectation, occupational sex segregation, and occupational immigrant concentration with the pursuit of a US master's degree among college-educated immigrants and natives. The analysis shows that while occupational female share was positively associated with postgraduate pursuit among natives, such relationship was weaker among immigrants with a foreign bachelor's degree. In contrast, occupational immigrant concentration was positively associated with postgraduate pursuit among foreign-educated immigrants but negatively among natives. The occupational share of workers with advanced degrees operated similarly between natives and immigrants. Moreover, these occupational effects varied more by immigration status than by gender. These findings underscore the host country's occupational contexts that generate different incentives and constraints for immigrants and natives to pursue a postgraduate degree. This adds nuance to the immigrant human capital investment model that posits immigrants will invest more in human capital than natives. The differential postgraduate investment between immigrants and natives in response to the occupational contexts yield implications for subsequent education-occupation match, career mobility, and economic stratification within the highly educated workforce.