Cholesterol crystal embolism (CCE) is a multivisceral disease caused by occlusion of small arteries with cholesterol crystal emboli deriving from eroded atherosclerotic plaques of the aorta and/or large feeder arteries. The factors precipitating CCE are manipulation of the aorta or other large arteries during arteriography or surgery, and anticoagulant or thrombolytic therapy. CCE has been reported to be a life threatening condition involving multiple vital organ dysfunction, including renal failure, cardiac failure, skin ischemic lesions such as livedo reticularis, patchy skin necrosis, and purple toes, gastrointestinal ischemia, and/or visual disturbance. We report a 63-year-old male patient of CCE after percutaneous transluminal coronary angioplasty, who contracted severe pneumonia of Pneumocystis carinii and Cytomegalo virus during steroid therapy (prednisolone 20 mg for 3 months). He was treated successfully with mechanical ventilation, hemodialysis, and appropriate antibiotic therapy. Although corticosteroid therapy has been reported to be effective in some CCE patients, the indications of steroid therapy, dosage of corticosteroids, duration of the treatment, or efficacy of prophylactic administration of antibiotics are not yet established. Further interventional studies are required in order to evaluate the benefit of corticosteroid therapy for CCE.