ImportanceFood insecurity on college campuses has emerged as an urgent public health priority; however, there has been a lack of studies focused on graduate students or postdoctoral trainees, particularly those enrolled at private academic institutions.ObjectiveTo estimate the prevalence of and factors associated with food insecurity among graduate students and postdoctoral trainees at a private academic university in Boston, Massachusetts.Design, Setting, and ParticipantsIn this cross-sectional survey study, a survey on food insecurity was sent to graduate students and postdoctoral trainees at 3 health-focused graduate schools at Harvard University during the end of the spring 2023 academic term (April to June). Participants were studying medicine, dental medicine, or public health. Data analysis was performed from July to September 2023.ExposureSociodemographic characteristics of graduate students and postdoctoral trainees.Main Outcomes and MeasuresThe primary outcome was food insecurity as assessed using the US Household Food Security Survey Module. Food insecurity also encompassed low and very low food security. Bidirectional stepwise logistic regression models were conducted to estimate the factors associated with food insecurity for graduate students and postdoctoral trainees.ResultsThe analytic sample included 1745 participants (response rate, 55%): 1287 were graduate students and 458 were postdoctoral trainees. The median age of respondents was 29.0 (IQR, 7.0) years, and more than half (1073 [61.5%]) identified as female. A total of 694 respondents (39.8%) identified as Asian, 625 (35.8%) as White, and 426 (24.4%) as being of other race or ethnicity. The prevalence of food insecurity was 17.4% (224 of 1287) among graduate students and 12.7% (58 of 458) among postdoctoral trainees. Among graduate students, factors associated with food insecurity included being Asian (OR, 1.06 [95% CI, 1.01-1.11]) or of other race or ethnicity (OR, 1.07 [95% CI, 1.02-1.13]), receiving financial aid (OR, 1.09 [95% CI, 1.05-1.13]), and having housing instability (OR, 1.53 [95% CI, 1.45-1.61]). Among postdoctoral trainees, factors associated with food insecurity included receiving Supplemental Nutrition Assistance Program benefits (OR, 1.59 [95% CI, 1.28-1.97]), having housing instability (OR, 1.33 [95% CI, 1.22-1.45]), and not owning a car (OR, 1.11 [95% CI, 1.04-1.18]).Conclusions and RelevanceIn this study, a substantial proportion of graduate students and postdoctoral trainees at a private academic institution experienced food insecurity during the academic year. These findings underscore the need for national and institutional interventions to address the complex, structural factors related to food insecurity in these distinct populations.