This study examined the relationship between family factors and secondary school students' aggressive and antisocial behaviours. Participants were 1,478 junior and senior secondary school students from four major urban centres in Botswana, aged 12-20. Results showed significant prevalence of self-reported aggressive tendencies and antisocial behaviours among secondary school students in Botswana. Boys rated themselves higher on aggression, use of alcohol and drugs and carrying and using dangerous weapons compared to girls. High scores on antisocial and aggressive behaviours were significantly related to poor parent-child relations and low parental monitoring. The results are consistent with findings from previous studies. The findings have important implications to violence prevention programs for children and adolescents. Suggestions for future research and the development of intervention programs are made.