Pyomyositis is an acute infection of skeletal muscles. It can be life-threatening if diagnosis and treatment are delayed. We present a case of a 23-year-old male delayed diagnosis of pyomyositis of the iliacus muscle and gluteal minimus muscle complicated with pulmonary septic embolism and septic shock who was treated with early goal directed cardiovascular resuscitation and surgical exploration combined with parenteral antibiotics. Computed tomography is useful in making the diagnosis. Early diagnosis and treatment may avoid surgery and reduce mortality.