Variations seen in the thoracic vein system are related to the development of these veins. During the dissection from the posterior mediastinum of the 60-year-old male cadaver, it was observed that there was no complete accessory hemiazygos vein, and both posterior intercostal veins and hemiazygos vein (above T10 level) drained bilaterally to the azygos vein. Considering these types of variations is important during imaging this region and surgical operations.