Background: Fatigue is frequent and disabling in adults with neuromuscular disorders, but not well characterized in paediatric neuromuscular disorders. Recently, fatigue was reported to be associated with poor health-related quality of life in children with Duchenne muscular dystrophy (DMD). Determinants of fatigue—a modifiable symptom—have not been studied in DMD. Our objective was to explore risk factors for fatigue in children with DMD. Methods: Patients aged 4–17 years identified via the Canadian Neuromuscular Disease Registry received mailed questionnaires. Fatigue was assessed using the PedsQLTM Multidimensional Fatigue Scale (patient- and parent-report). Standardized measures for depressive symptoms, sleep disturbances, functional ability and physical activity were used. Spearman’s correlations and Wilcoxon rank-sum tests were computed. Results: Of 194 eligible patients, 64 have responded to date. DMD patients reported greater fatigue than healthy controls from published data. Depressive symptoms were associated with greater fatigue, by patient-report (ρ=-0.44, P<0.001) and parent-report (ρ=-0.40, P=0.002). Sleep disturbances were associated with greater fatigue, by patient-report (ρ=-0.41, P=0.007) and parent-report (ρ=-0.51, P<0.001). Greater functional ability was associated with less fatigue, by parent-report (ρ=0.30, P=0.02). Physical activity and ambulatory status were not associated with fatigue. Conclusions: Fatigue is a significant issue in DMD. Depressive symptoms and sleep disturbances are associated with fatigue, warranting attention in therapeutic strategies to reduce fatigue.