Seeking help for mental health concerns is critical for improving wellbeing and preventing the development of mental health disorders, yet many adolescents with mental health problems fail to seek professional help. It is well established that young people with mental health problems face a variety of barriers to help-seeking; however, little is known about the ways in which these barriers interact to impact upon the help-seeking process. Guided by the reasoned action approach, this study investigated the predictive relationship between factors that influence help-seeking. Results revealed that mental health knowledge significantly predicted help-seeking intentions, while attitudes did not. Gender differences were identified for help source preferences. The current study contributes to knowledge on the relationship between key variables that influence the adolescent help-seeking process. Findings highlight the importance of mental health knowledge in predicting help-seeking intentions and provide support for interventions that focus on improving mental health literacy in adolescents.