Background: College students are at-risk populations of mental health problems and risky sexual behaviors. However, little literature focuses on the association between mental health problems and risky sexual behaviors. Our study examined the association between mental health problems (depressive symptoms, suicide, and mental disorders) and risky sexual behaviors among a large sample of Chinese college students. Methods: A total of 49,728 Chinese college students (47.5% male) eventually participated in the analysis. A self-administered questionnaire was used to measure mental health, risky sexual behaviors (casual sex, no condom use at last sexual intercourse, group-sex, and a high number of sexual partners), and other sociodemographic characteristics. Logistic regression analysis was used to explore the relationship between mental health and risky sexual behaviors. To ensure the data is representative of the nation?s statistics, all analyses were weighed. Results: The prevalence of depressive symptoms, suicide ideation and suicide attempts, and mental disorders was 42.83%, 41.29%, and 7.74%, respectively. 26.13% of participants were sexually active in the previous twelve months. Nearly 35% of sexually active participants were engaged in risky sexual behaviors. Logistic regression results demonstrated that mental health problems were associated with risky sexual behaviors after adjusting confounders. Limitations: cross-sectional analysis; The self-reported variables may be subject to recall bias and fraud. Conclusions: There is a relatively high prevalence of mental health problems and risky sexual behaviors amongst Chinese college students. A significant association between mental health problems and risky sexual behaviors was suggested by our study. Our findings support the importance of advocating for mental and reproductive healthcare for college students.