"Background and Aim: The prevalence of high-risk behaviors is one of the most serious issues threatening the health of young people. The first step in preventing youth risk-taking is to recognize the problem and its dimensions. The purpose of this study was to investigate high-risk behaviors among students at Tehran’s universities. Methods: This cross-sectional descriptive-analytical study was conducted from March to August 2019. The sample set was 4,000 students. Data was collected by multi-stage sampling at eight universities in Tehran. Demographic information and standard youth-risk questionnaires were used. SPSS 19 software was used to perform an independent t-test, Pearson ANOVA, and linear regression at a significance level of 0.05 on the questionnaire data collected. Results: The mean of the total tendency to high-risk behavior was 130.34±40.37. Significant risks identified were driving (27.3±8.33), violence (18.86±6.4), smoking (18.86±7.68), drugs (22.47±8.83), alcohol (24.10±8.57), and high-risk sexual behavior (18.47±7.49). High-risk behaviors were more common in men, single people, and people living in dormitories (P<0.05). Age and gender were the best-correlated predictors of students' high-risk behaviors. Conclusions: Results show that the tendency to high-risk behaviors in students is a worrying situation. as, at younger ages, the tendency to engage in high-risk behaviors is greater. Among young men and in dormitory life, students are more prone to high-risk behaviors. So, more monitoring in dormitories, especially male dormitories, and better planning and education to reduce high-risk behaviors among students, is necessary "