Venous aneurysms are uncommon but they can have devastating consequences, including pulmonary embolism, other thromboembolic events and death. We report six cases of venous aneurysm of the extremities, in which the first sign of presence was acute pulmonary embolism. Surgical resection is recommended whenever possible. Our experience suggests that prophylactic surgery is cautiously recommended for low-risk patients with venous aneurysms of the abdomen and strongly recommended for extremity deep and superficial venous aneurysms for their potential risk of developing thromboembolic complications despite adequate anticoagulation. Other venous aneurysms should be excised only if they are symptomatic or enlarging.