Abstractactually scant. This study aimed to correlate the diagnostic accuracy of ultrasonography with electrodiagnosis in both DM and non-DM CTS patients. Patients and Methods: Thirty six non-diabetic patients and twenty five diabetic patients with CTS were assessed. All patients were subjected to electrophysiological assessment of wrists and grayscale ultrasonography (US).Results: High mean cross sectional area of median nerve (CSA) on ultrasonography was detected with nonsignificant difference between both groups. A non-significant difference for flattening ratio was found between two groups. There was a highly significant positive correlation between electrodiagnosis and ultrasonography in diabetic patients. Conclusion:The CSA of median nerve is larger in CTS hands in both DM and non-DM patients. The combination of electrophysiology and ultrasonography provides diagnostic effective tools across the entire spectrum of CTS in diabetic and non-diabetic patients.