Dentatorubral pallidoluysian atrophy is a neurodegenerative disease that generally presents in adulthood. Although rare, it can be observed in childhood due to extreme expansion of the triplet repeat size during spermatogenesis. The diagnosis in childhood is very difficult in the absence of family history. Here we describe a 12-year-old girl with dentatorubral pallidoluysian atrophy who presented with progressive myoclonic epilepsy and ataxia. Family history exhibited similarly affected cases on the paternal side. Molecular testing for dentatorubral pallidoluysian atrophy revealed abnormal "cytosine-adenine-guanosine" expansion in the atrophin-1 gene.