Fibrodysplasia ossificans progressiva (FOP) is a rare autosomal dominant disorder of skeletal malformations and presents progressive extra-skeletal ossification. The 617G>A (R206H) mutation in the activin receptor type IA (ACVR1) gene has been identified in all examined individuals with FOP of various ethnic groups, including Caucasian and Chinese descents. Here, we examined three Japanese patients with FOP for ACVR1 mutations. We identified the 617G>A mutation in all three patients. Our results suggest that the mutation in the ACVR1 gene is common and recurrent in the global population.