Objective: To investigate sex and racial/ethnic differences in overweight and obesity in college students. Participants: A nationally representative sample of 319,342 U.S. college students (mean age = 20.4 years; 67.7% female) from Fall 2011 to Spring 2015. Methods: A secondary data analysis of multi-year cross-sectional data was performed. Multiple logistic regression was used to examine factors (e.g. cumulative grade average, year in school, and living place) associated with overweight and obesity determined from BMI calculated by self-reported height and weight. Results: The prevalence of overweight and obesity was significantly higher for both sexes in Spring 2015 than in Fall 2011. Significant differences were found in overweight and obesity by sex and race/ethnicity. Higher adjusted odds ratios for overweight and obesity were observed for men, blacks, and Hispanics (compared to whites). Asians had the lowest adjusted odds of overweight and obesity. Conclusions: Intervention strategies for the prevention and management of overweight and obesity in U.S. college students should consider sex and racial/ethnic inequalities.