Abstract. [Purpose] To determine whether position affects measured lung capacity of spinal cord injury patients.[Subjects] The study subjects were 45 patients with spinal cord injury (cervical level 15, thoracic level 15, lumbar level 15). Subjects were provided with a full explanation of the experimental procedures and all provided written consent signifying their voluntary participation.[Methods] We used a spirometer (Spirometer, Micromedical Ltd, UK) to measure pulmonary function in the supine and sitting positions (straightened upper body at an angle of 90°). Forced vital capacity (FVC), forced expiratory volume during the first second (FEV1), tidal volume (TV), and maximum insufflation capacity (MIC) were also measured.[Results] FVC, FEV1, TV, MIC (%) were greater in the supine than in the sitting position for those with injury at the cervical or thoracic injury level. On the other hand, FVC, FEV1, TV, MIC (%) were lower in the supine position for those with an injury at the lumbar level. [Conclusion] More attention should be paid to the effect of injury level on measured lung capacity.