Primary pyomyositis is a deep bacterial pyogenic infection of the skeletal muscles that can cause abscess formation. Due to the indefinite nature of the symptoms and signs of pyomyositis, the diagnosis is difficult to make. A 57-year-old male patient with a 10-year history of type 2 diabetes mellitus was seen with a complaint of right calf pain, swelling, and stiffness that was present for 2 months. Temperature was 38.2 degrees C. Hommans sign was positive and peripheral pulses were palpable. Laboratory values showed a white blood cell count of 18300/mu L, an erythrocyte sedimentation rate of 85 mm/h, and a CRY of 18.3 mg/dL. MRI showed a 26 X 8-cm abscess and an 8 X 5.5-cm focus of pyomyositis inside the gastrocnemius muscle. Parenteral amikacin+sulbactam-ampicillin was begun. Culture revealed Staphylococcus aureus.