The aim of the study was to compare urodynamic findings and upper urinary tract (UUT) abnormalities detected by ultrasonography in complete and incomplete suprasacral spinal cord injury (SCI) patients with neurogenic detrusor overactivity. Thirty-eight suprasacral SCI patients who underwent ultrasonography evaluation of the UUT and urodynamic investigation were evaluated retrospectively. The mean maximum detrusor pressure was 51.08+28.71 cmH[subscript 2]O for the American Spinal Injury Association (ASIA)-A group and 61.42+30.93 cmH2O for the ASIA-B-E group (P less than 0.05). The mean cystometric capacity was 269.38+139.98 for the ASIA-A group and 223.36+135.59 ml for the ASIA-B-E group (P less than 0.05). Abnormalities in the UUT were found in 15.4% of the complete SCI patients and 16% of the incomplete SCI patients (P less than 0.05). No differences were found in urodynamic parameters and UUT abnormalities between the complete and the incomplete suprasacral SCI patients. Therefore, incomplete SCI patients should be observed with the same caution as complete SCI patients.