Background. Despite a growing body of research from the United States and other industrialized countries on the inverse association between supportive social relationships in the school and youth risk behavior engagement, research on the measurement of supportive school social relationships in Central America is limited. We examined the psychometric properties of the Student Perceptions of School Cohesion (SPSC) scale, a 10-item scale that asks students to rate with a 5-point Likert-type response scale their perceptions of the school social environment, in a sample of public secondary school students (mean age = 15 years) living in central El Salvador. Methods. Students (n = 982) completed a self-administered questionnaire that included the SPSC scale along with measures of youth health risk behaviors based on the Center for Disease Control and Prevention's Youth Risk Behavior Survey. Exploratory factor analysis was used to assess the factor structure of the scale, and two internal consistency estimates of reliability were computed. Construct validity was assessed by examining whether students who reported low school cohesion were significantly more likely to report physical fighting and illicit drug use. Results. Results indicated that the SPSC scale has three latent factors, which explained 61.6% of the variance: supportive school relationships, student-school connectedness, and student-teacher connectedness. The full scale and three subscales had good internal consistency (rs= .87 and = .84 for the full scale; r sand between .71 and .75 for the three subscales). Significant associations were found between the full scale and all three subscales with physical fighting (p .001) and illicit drug use (p < .05). Conclusion. Findings provide evidence of reliability and validity of the SPSC for the measurement of supportive school relationships in Latino adolescents living in El Salvador. These findings provide a foundation for further research on school cohesion and health risk behavior in Latino adolescents living in the U.S. and other Latin American countries.