qMRI of skeletal muscle has shown promising results in other neuromuscular diseases, but multi-parametric imaging has not been executed in Spinal Muscular Atrophy. We investigated a cohort of 31 patients and 20 controls with protocol consisting of DIXON, T2 mapping and DTI on a 3T MR scanner. All parameters differed significantly between patients and controls. DTI elucidates distinct properties of the muscle, suggesting atrophy by a lowered MD and increased FA. DTI shows correlation with muscle strength and motor function. This suggests the potential of diffusion tensor imaging of muscle in monitoring disease progression in SMA.