Septic pulmonary embolism is an uncommon disorder in which septic thrombi are mobilized from an infectious nidus and transported in the vascular system of the lungs. We report a case of a 52-year-old immunocompetent female who suffered from septic pulmonary embolism associated with polymyositis, deep venous thrombosis and pericardial effusion. Oxacillin-sensitive staphylococcus aureus (MSSA) was isolated from her sputum. Clinical presentation improved after incision of the muscle abscess and vancomycin treatment.