Background: Mental health problems among college students represent an important and growing public health concern for which epidemiological data are needed. Objectives: This cross-sectional study aimed to estimate the prevalence of mental health problems among undergraduate college students at King Faisal University, Saudi Arabia and to determine the socio-demographic and other potential correlates for mental health problems. Materials and Methods: A total of 1696 undergraduate students of both genders from ten colleges at King Faisal University were selected using a random sampling method. Participants were assessed for depression and anxiety using the Patient Health Questionnaire (PHQ) anonymously. Information was also collected for the socio-demographics, presence of chronic disease conditions and other potential correlates as financial, personal and family problems. Results: The prevalence of symptoms of any depression or anxiety was 21.9%. Symptoms of major depression were present in 9.9%, other depression in 19.4% and any depression among 24.4%. Panic and generalized anxiety symptoms were found in 4.0% and in 14.0% respectively. Suicidal ideation in the past four weeks was reported by 1.1% of students. Major depression and anxiety were significantly higher among females. Multivariate regression logistic models revealed that the type of college (nature of received education), female gender, financial and personal problems were significant predictors for major depression. Conclusion: These findings highlight the need to address mental health problems in young adult populations, particularly among those of lower socioeconomic status.