Abstract Gluteal intramuscular myxomas with MR images have not been reported before. A 45-year-old man presented with a palpable mass in his right buttock for several months. Magnetic resonance imaging showed an intramuscular cystic lesion with homogeneous signal intensity at the right gluteus muscle, and the mass had thin peripheral enhancement after gadolinium administration. The patient was treated by marginal excision of the tumor. Histologic diagnosis was compatible with intramuscular myxoma.