We have experienced a case of intramuscular hemangioma in the psoas muscle. Intramuscular hemangiomas are relatively uncommon, compared to cutaneous or hepatic hemangiomas. Although all muscules can be affected, it is common in muscules of the lower extremities, particularly those of the thigh. It is rare that intramuscular hemangioma occurs in the iliopsoas muscle. A 50-year-old woman was seen at the hospital because of numbness of the right lower extremity. CT scan showed a large mass in the iliopsoas muscle. Magnetic resonance imaging scan showed a high intensity mass both on T1 and T2. We suspected liposarcoma of the psoas muscles, and performed a wide resection including the psoas muscles. The removed tumor was about 6×4 cm in diameter, and it looked like a lipoma. Histopathological appearances included various sizes of vesseles growing invasively into muscles and a lot of fat cells, but no malignant cells were seen in the tumor. Definite diagnosis of intramuscular hemangioma was made.