Pyomyositis is an acute bacterial infection of skeletal muscle, usually caused by Staphylococcus aureus. It is common in the tropics but rare in temperate climates. In temperature climate there are predisposing factors, such as diabetes, HIV infection, malignancy. The incidence of reported bacterial pyomyositis is increasing in recently, especially among immunocompromised persons such as HIV infection or diabetes mellitus. We experience multifocal pyomyositis in 49-year-old man with type 2 diabetes mellitus presented with drowsy mental state. Muscular USG and MRI finding shows multifocal abscess in thigh. Blood culture revealed Staphyloccus aureus. And patient received a intravenous broad-spectrum antibiotics, incision and drainage. He was successfully managed with drainage and antibiotics then discharge. Since diabetes or infection with HIV predisposes patients to bacterial infection, pyomyositis will occur more frequently. Increased awareness if the disease will improve management.