We treated a 37 year old woman with venous aneurysm along left side of the neck. In the beginning, she was asymptomatic and with increase in size of the venous aneurysm she experienced severe pain. Pathohistological examinations revealed a destructive change of the venous wall and thrombosis. Therefore, in cases of venous aneurysm along the neck, such aneurysm should probably be treated surgically to prevent the occurrence of pulmonary embolism.