Introduction: according to literature, adolescence is a period where the young are more likely to engage in behaviors that could endanger their health. In addition, there is evidence suggesting the impact of some factors of family environment on the presence of risk behaviors. Objetive: the aim of this study was to determine changes in risk behavior and analyze the differences in family factors on these behaviors. Method: we used a longitudinal study on a group of 6,089 students (37.5% men and 62.5% women). Risk behaviors were assessed with 10 indicators. Family factors were evaluated by three scales: support, relationship and substance abuse within the family context. The information was obtained in a previous session prior to the beginning of the scholar semester for each of the three analyzed events. Results: an increase in risk behaviors was observed over time. Further, we also found significant differences in family factors on risk behaviors in the three measurements. Discussion: this evidence will allow the development of prevention and early detection programs to treat several problems related to teenagers during their school career.