Superficial lipoma was easy to diagnose, but deep lipoma, especially intraosseus lipoma, was difficult to detect pre-operatively. Intraosseous lipoma is very rare and had been difficult to differentiate from other tumors before image diagnosis was developed. Recently, the detecting ratio has increased due to advanced diagnostic tools. Preoperative diagnosis is crucial for the treatment plan and influences the approach method for excision. We experienced one case of misdiagnosis which was diagnosed as intraosseous lipoma according to the preoperative MRI but turned out to be a parosteal lipoma after the surgery.