The presence of antiphospholipid antibodies is associated with arterial and venous thrombosis. A young female with initial presentation of dyspnea and cough that lasted for days is reported. A computed tomographic scan of her chest and echocardiography showed features of thrombus formation over the right atrium, complicated with pulmonary thromboembolism. Antiphospholipid syndrome was diagnosed according to elevated activated partial thromboplastin time, high serum titers of anticardiolipin antibody, and the presence of intracardiac thrombus with pulmonary embolism. This thrombus was subsequently removed successfully with surgical intervention, and the patient's recovery was uneventful.