PURPOSE: To evaluate the change of intra-abdominal pressure related with intravesical and intrarectal pressure in patients with spinal cord injury according to daily activities and postural changes which make the abdominal pressure elevated. MATERIALS AND METHODS: Ten subjects with lower thoracic and lumbar spinal cord injury were enrolled. Their mean age was 38 years. The urodynamic study was performed and the intravesical and the intrarectal pressures were measured with a double lumen catheter and a intrarectal probe. The intravesical and the intrarectal pressure were obtained during patient's speech, sneeze, cough, valsalva and various postural changes with supine to decuitus, decubitus to supine, supine to sit, and sit to supine according to empty and full bladders, respectively. RESULTS: The order of higher intravesical and intrarectal pressure rise during various maneuvers were valsalva, sneeze, supine to sit and cough, respectively. Higher correlation coefficient between the intravesical and intrarectal pressures were noted during cough, sneeze, valsalva and supine to sit in empty bladder than full one. CONCLUSION: These results demonstrated that the intravesical and intrarectal pressures were influenced by daily activities and postural changes of increasing the intra-abdominal pressure. The intrarectal pressures according to daily activities such as cough, sneeze, valsalva and postural change were significantly related with intravesical pressures.