Intraosseous lipomas are extremely rare and this incidence has been reported to be less than one per 1,000 primary bone tumors. Because of its rarity, information of this tumor is obtained from case reports. We report a case of intraosseous lipoma that developed in the proximal humerus. The patient was a 69-year-old male who had experienced night pain and intermittent pain at the proximal humerus for 10 years. Simple x-ray revealed a well demarcated osteolytic lesion, which was measured 4 cm in width with a central calcific lesion. There was no cortical destruction in the proximal humerus. He was treated by currettage without bone graft, thereafter his symptoms were relieved.