Anxiety and depressive disorders are the most common mental health disorders in adolescents, yet only a minority of young people with these disorders access professional help. This study aims to address this treatment gap by improving our understanding of barriers and facilitators to seeking/accessing professional help as perceived by adolescents with anxiety/depressive disorders identified in the community. Twenty-two adolescents, aged 11–17 years, who met diagnostic criteria for a current anxiety and/or depressive disorder were identified through school-based screening. In-depth qualitative interviews were conducted one-to-one with each adolescent and adolescents’ parents were interviewed separately for the purpose of data triangulation. Data were analysed using reflexive thematic analysis. We identified four themes capturing adolescent perceived barriers and facilitators to seeking/accessing professional help for anxiety and depressive disorders: (1) making sense of difficulties, (2) problem disclosure, (3) ambivalence to seeking help, and (4) the instrumental role of others. Barriers/facilitators identified within each theme reflect important developmental characteristics of adolescence, such as a growing need for autonomy and concerns around negative social evaluation. At the same time, the results highlight adolescents’ dependency on other people, mainly their parents and school staff, when it comes to successfully accessing professional help for their mental health difficulties. This study identifies a number of barriers/facilitators that influence help-seeking behaviour of adolescents with anxiety and/or depressive disorders. These factors need to be addressed when targeting treatment utilisation rates in this particular group of young people.