Orofaciodigital syndromes have many clinical and cephalometric anomalies, including facial irregularities, oral cavity abnormalities, and malformations of fingers and toes. In this case of twin girls, buccal exploration, cephalometric examination, and genetic analysis were performed to diagnose Orofaciodigital I or Orofaciodigital II syndrome. Clinically, the twins had several dental and skeletal irregularities. Genetic analysis revealed a DNA segment abnormality corresponding to exon 3 and presence of nucleotide change, 243C>G, leading to the missense mutation H81Q. This causative mutation associated with the OFD1 gene has not been reported previously. Both patients were diagnosed as having Orofaciodigital I syndrome.