A 45-year-patient who suffered from old myocardial infarction (OMI) associated with systemic lupus erythematosus (SLE) and arterio-sclerotic obstruction (ASO) had unstable angina. Emergent coronary artery bypass grafting (CABG) was performed using saphenous vein graft because the left inter mammary artery was possible to be the collateral source for ASO. A high grade fever occurred without return of SLE 9 days after the operation. Pancytopenia simultaneously occurred. Hemophagocytic syndrome was diagnosed by the bone marrow examination. Pulse therapy with steroids was given and it was remarkably effected. Hemophagocytic syndrome has high mortality. However, it is difficult to distinguish from the other disease with high fever and bone marrow suppression in early period. Therefore, bone marrow examination was required to diagnose and to start the appropriate therapy as soon as possible.