OBJECTIVE The authors examined the national prevalence of gambling problems and sports wagering among US college student-athletes. PARTICIPANTS A national sample of 20,739 student-athletes participated in the study. METHODS The authors used data from the first national survey of gambling among college athletes, conducted by the National Collegiate Athletic Association. RESULTS Men (62.4%) consistently had higher past-year prevalence of gambling than did women (42.8%). The authors identified 4.3% of men and 0.4% of women as problem or pathological gamblers. Among the most popular forms of gambling were playing cards, lotteries, and games of skill, with male-to-female prevalence ratio ranging 1.3-5.6 across various gambling activities. Athletes in golf and lacrosse were more likely to report sports wagering than were other athletes. Athletes in gender-specific sports wagered more prevalently than did athletes in unisex sports. CONCLUSION Gambling prevalence may be underestimated in this population because respondents' athletics eligibility is at stake. This study provides important baseline data for future cohorts of athletes.