Avascular necrosis, which is caused by non-traumatic factors, is not a specific disease entity but the final common result of many conditions leading to death of bone cells by the impairment of blood supply. Although associated diseases and conditions (steroid administration, alcoholism, systemic lupus erythematosus, etc.) are well known, avascular necrosis is thought to arise from a multifactorial etiology of mechanical, hormonal and hematologic factors. The goals of treatment are to maintain range of motion, to stop the progression of disease, and to reduce symptoms. If conservative treatment fails, arthroscopic debridement, core decompression, grafting, and arthroplasty are surgical alternatives according to the stage of disease. Because of light loading, symptoms and functional loss in humeral head necrosis are fewer when compared with femoral head avascular necrosis. Most patients can sustain their lives with simple exercies.