Objective: This study was aimed to determine risky behavior for health in the students of Ondokuz May's University (OMU). Material and Methods: In this cross-sectional study, information about socio-demographic characteristics and risky behavior for health was collected from 2050 students, which constitute 85.4% of the total student population, by a questionnaire under supervision; and t test and the chi-square test in independent groups were used in the statistical evaluation. Results: Among students attending the study, 1029 (50.2%) were males, 1021 (49.8%) were females, and the mean age was calculated as 21.1 +/- 1.9 years. It's found that most of the students (85.9% and 61.8%) were not using helmets while riding a bicycle or a motorcycle. They were not fastening seat belts while traveling in a vehicle (25.4%), carried weapons at least once in the previous month (5.2%), involved in physical fight at least once in the previous month (10.0%), smoked and had alcohol in the previous month (%22.9-24.2), insufficiently consumed fruit-vegetables in the last seven days (28.6%); Having sexual intercourse (21.6%) was significantly more frequent in males; insufficient physical exercise in the last seven days (66.4%), and going on a diet to lose weight in the last month (17.9%) were significantly more frequent in female students. Conclusion: Research data reveals high prevalence of some health-threatening risky behaviors among university students, and indicates the necessity of effective education programs on road safety, nutrition and health, health effects of smoking, alcohol consumption and other substance abuses, and safe sex/sexually transmitted diseases.