Diabetic striatopathy is a well-known complication of diabetes in adults. To our knowledge, only 2 cases have been reported in children. We here report the case of a teenager in whom diabetic striatopathy was revealed by the subacute appearance of hemichorea-hemiballism in the context of weight loss, polyuria, and polydipsia. Glycemia control allowed rapid clinical recovery despite established striatal lesions documented on MRI. We also discuss current hypotheses about pathophysiological processes underlying this entity.