Objective: The present study examined the longitudinal relations between illness perceptions and asthma control and emotional problems (i.e., anxiety, depression, stress), respectively, in adolescents with asthma. Furthermore, the mediating effects of asthma-specific coping strategies on these relations were examined, as specified in the Common Sense Model (CSM). Methods: In 2011, 2012, and 2013, adolescents (aged 10-15) with asthma were visited at home (N = 253) and completed questionnaires about their illness perceptions, asthma-specific coping strategies, asthma control, symptoms of anxiety and depression, and perceived stress. Path analyses were used to examine the direct relations of illness perceptions with asthma control and emotional problems and the mediating effects of coping strategies cross-sectionally and longitudinally. Results: Perceptions of less perceived control and attributing more complaints to asthma were associated with better asthma control. Perceptions of more concern, less coherence, and increased influence of asthma on emotional well-being were associated with more emotional problems. Longitudinally, perceptions of more treatment control and fewer concerns predicted less emotional problems over time. More worrying mediated the cross-sectional relation between perceiving more concern about asthma and less asthma control and the longitudinal relation between perceiving more concern about asthma and more emotional problems. Conclusion: Illness perceptions were associated with asthma control and emotional problems; however, over time, illness perceptions only predicted changes in emotional problems. Most coping strategies did not mediate the relation between illness perceptions and outcomes. Interventions aimed to change illness perceptions in adolescents with asthma could decrease emotional problems.