The most common electrocardiographic (ECG) findings in acute pulmonary thromboembolism (PTE) are right bundle branch block, T wave, and ST-segment changes. Complete atrioventricular (AV) block has hitherto been reported in only one patient with PTE. A 63-year-old female patient presented with recurrent syncope and sudden-onset dyspnea. There was complete AV block in the admission ECG. She never had similar complaints before and an ECG taken three months before was completely normal. A temporary pacemaker was placed through the femoral vein. Physical and laboratory findings were suggestive of acute pulmonary embolism. Pulmonary artery angiography demonstrated nearly total occlusion of the proximal right pulmonary artery. Her coronary arteries were normal. Thrombolytic therapy with streptokinase infusion followed by standard heparin infusion resulted in clinical improvement and resolution of complete AV block. The patient was discharged on the 15th day with oral warfarin treatment.