The incidence of extramammary Paget's disease (EMPD) is very low. An 84-year-old Korean man was treated with topical and oral medications at a local dermatologic clinic for a year, but the symptoms did not improve. He visited Severance Hospital and underwent a perianal skin biopsy and was finally diagnosed with EMPD. The authors performed a wide local excision according to a 1-cm margin around the lesion. For the skin and the soft tissue defects, bilateral inferior gluteal artery perforator flap transpositions were performed. The size of the lesion was 14 cm(2) × 9 cm(2), and the lateral and the basal margins were all disease free.