We report a 36-year-old woman with a 1-year history of systemic lupus erythematosus who was admitted with acute onset of dyspnea and chest pain. She presented with a classic medical history of antiphospholipid antibody syndrome, including spontaneous abortion, deep venous thrombosis, and clinical manifestations of lupus activation. The differential diagnosis was made after a detailed history and examinations with transthoracic/transesophageal echocardiography, deep venous ultrasonography, chest computed tomography, and coronary angiography. This case demonstrates a left ventricular apical thrombus in angiographically normal coronary arteries and also deep vein thrombosis causing acute pulmonary thromboembolism. Antiaggregant and anticoagulant therapies were initiated as a result of the presence of a left ventricular apical thrombus and deep venous thrombosis, which is predisposed to recurrent pulmonary or systemic embolization. Control echocardiography demonstrated resolution of apical thrombus and normalized left ventricular systolic function after aspirin, warfarin, and immunosuppressive therapy for 2 months.