Purpose It is not completely clear whether and how medication adherence, asthma control, and quality of life (QOL) predict each other over time. Therefore, the aim of the present study was to examine the longitudinal associations between asthma control, medication adherence, and quality of life among adolescents. Methods In this 3-wave longitudinal study, adolescents (N = 139, Mean age = 11.8) completed questionnaires about their medication adherence (Medication Adherence Report Scale for Asthma), asthma control (Asthma Control Questionnaire), and QOL (Adolescent Asthma Quality of Life Questionnaire) during home visits in the spring/summer of 2011, 2012, and 2013. Cross-lagged analyses examined temporal interrelations between the three variables over the course of 3 years. Results Higher QOL at baseline predicted increased medication adherence at follow-up (T2), but did not predict changes in asthma control over time. Medication adherence and asthma control did not predict changes in QOL over time. There were no associations between asthma control and medication adherence over time. Conclusions Interventions could focus on increasing QOL to increase medication adherence in adolescents with asthma.