Idiopathic avascular necrosis (AVN) of the capitate bone is an important, although rare, cause of spontaneous onset of wrist pain. Most cases involve direct or indirect trauma. Only a few reports of idiopathic avascular necrosis have been published. We present a case report of a 32-year-old woman who presented with a chief complaint of a left wrist pain, swelling and loss of all ranges of motions for approximately 1 year. She had no history of prior wrist trauma or steroid use. Laboratory testing for systemic disease or infection were negative. Diagnosis of avascular necrosis of the capitate has been made via plain film radiology, isotope bone scanning, and computed tomography scan. No etiologic factor could be identified. Surgical treatment was recommended, given drilling and autogenous bone grafting. Histological analysis showed necrotic bone. The physical therapy was implemented to restore function. Two months postoperatively, she was almost pain free.