Background: The major modifiable risk factor for skin cancer is excess ultraviolet radiation (UVR) exposure. Athletes, particularly outdoor athletes, are at increased risk for skin cancers due to heightened UVR exposure. Little is known about sun exposure and sun-protective behaviors among collegiate athletes. Between 2012-2023 Stanford University athletes completed surveys on their sun exposure, as well as their sun-protective beliefs and behaviors. We seek to determine whether collegiate athletes’ exposure to UVR and sun-protective behaviors have changed over those years. Methods: Scores for sun protection (ranged from 0-14 based on responses to 7 questions) and time training outdoors (hours/year) were developed. Adjusted multiple linear regressions evaluated trends in sun protection and sun exposure scores over time for all athletes, outdoor athletes, and indoor athletes separately. Results: A total of 2,689 athletes completed the surveys. Mean hours per year spent training outdoors was 291.5 for all athletes, 347.7 hours for outdoor athletes and 48.7 for indoor athletes. The mean protection score was 9.9 overall, 9.4 among outdoor athletes, and 12.1 among indoor athletes. No significant trend in outdoor training hours was observed over the 10 years for all athletes; however, outdoor athletes reported increased outdoor UVR exposure over time (Ptrend<0.01). A positive trend was observed in protection scores for outdoor (Ptrend=0.05), and all athletes (Ptrend =0.02) indicating an increased use of sun-protective practices including use of sunscreen and sun-protective clothing. Conclusions: These results suggest structural and policy-based changes are needed to decrease UVR exposures among collegiate athletes.