Objective: To compare college students' perceived disease risk with disease prevalence rates. Methods: Data were analyzed from 625 college students collected with an Internet-based survey. Paired t-tests were used to separately compare participants' perceived 10-year and lifetime disease risk for 4 diseases: heart disease, cancer, diabetes, and overweight/obesity. Results: Respondents estimated their risk of developing heart disease as lower than cancer, yet rated their risk of developing heart disease as higher than diabetes and being overweight/obese. Conclusion: Incongruence between college students' perceived disease risk and disease prevalence rates calls for improved public health education.