Scientific evidence suggests that certain psychological factors may contribute to the occurrence of high-risk behaviors among adolescents. This study aimed to determine the high-risk behaviors and their relationship with psychological factors in Iranian high school students. This cross-sectional study involved 1100 high school students (564 boys and 536 girls). The subjects were selected from a total population of 9488 students using a multistage sampling method. Data was collected through a general information questionnaire (GIQ) and the Iranian Adolescents Risk-Taking Scale (IARS). The GIQ consisted of two parts: demographic information and psychological factors. These factors, including false self-confidence, excitement-seeking, risk-taking, experimentation, curiosity, heroism, disappointment with the future, handsomeness, tiredness of monotony, and enjoyment, were extracted with a deductive-centered approach by reviewing the literature. Descriptive statistics (absolute and relative frequency, mean, and standard deviation) and inferential statistics (independent t-test and multiple linear regression) were used for data analysis. The results showed that the total mean score of high-risk behaviors was 62.12, lower than the middle scale. The highest mean score of high-risk behaviors was associated with a tendency to dangerous driving, while the lowest mean score was related to the tendency to drug abuse. All psychological variables demonstrated a statistically significant relationship with high-risk behaviors (P < 0.001). In the multiple linear regression model, all psychological variables except risk-seeking and handsomeness remained significant predictors of high-risk behaviors. These variables included false self-confidence, excitement-seeking, experimentation, curiosity, heroism, disappointment with the future, tired of monotony, and hedonism. They explained 29% of changes in high-risk behaviors. Among these variables, excitement-seeking was the most effective in predicting high-risk behaviors. Most of the psychological variables in the present study explained high-risk behaviors. Paying attention to these variables can provide a more comprehensive view for parents and experts whose goal is to provide educational and counseling programs to reduce high-risk behaviors among adolescents.