A cross-sectional study was conducted to evaluate factors associated with safe sex among sexually active public school students in Minas Gerais State, Brazil. The study focused on correlations between the variables gender, age, schooling, current grade, ethnicity, religion, importance attributed to religion, mothers' education, prior exposure to any sex education, promotion of juvenile protagonism, and participation by health professionals in school activities and consistent condom use with casual or stable partners and with use of other modern contraceptive methods. Bivariate and multivariate logistic regression analyses were used. Male gender and participation by health professionals in school activities were positively associated with all indicators of safe sex, and maternal schooling of more than eight years was positively associated with consistent condom use with casual and stable partners. Secondary (versus elementary) schooling and age (older) were inversely associated with consistent condom use with casual and stable partners, respectively. Ascribing greater importance to religion and Evangelical religion were negatively associated with use of modern contraceptives in the last sexual intercourse.2314351