This study investigated influence of personality and family types on adolescent at-risk behaviours. The study’s design is Ex-post-facto design. The study’s population is 200 adolescents who showed traits of developing at-risk behaviours. Adolescents Risk-Taking Behaviour Index and Neo-Personality inventory was used to collect data for the study. One hypothesis was formulated for the study. The data collected was analyzed using multiple regression statistics. The analysis showed that, neuroticism personality influences at-risk behavior, while extraversion and openness to experience do not. From the findings , it was recommended that, schools should initiate prevention programmes that are designed to enhance factors that are protective in nature and move towards reversing or reducing known risk factors.