Abstract: Objective To evaluate the diagnostic sensitivity of neuroelectrophysiological test in diabetic peripheral neuropathies (DPN), motor conduction velocity (MCV) and F response were comparatively investigated between diabetes mellitus (DM) and healthy subjects.Methods DM group had 222 cases (male 120, female 102), aged from 18 to 85 years and control group had 155 healthy subjects (male 76, female 79), aged from 18 to 82 years. MCV of the madian, ulnar, peroneal and tibial nerves were measured and F waves were elicited using Keypoint electromygraphy. Distal and Proximal latency, MCV, F wave latency (FwPL), duration between F and M waves(F MIPL), F wave conduction velocity (FCV) and F wave ratio were analyzed.Results (1)The abnormality rates of MCV in madian, ulnar, peroneal and tibial nerves in DM group were 51 4%,51 6%,68 5% and 45 2%, and the abnormality rates of F wave were 52 7%,58 0%,53 0% and 63 9%,respectively. (2)The abnormality rates of all F response parameters recorded from the four nerves and the abnormality rates of MCV recorded from tibial and peroneal nerves were increased. (3)There was no significant difference in F wave ratio between DM and control group (P>0 1). (4)75 2% of all the patients in DM group showed one or more abnormalities in MCV or F wave parameters, and electrophysiological abnormalitis correlated with, or precede to clinical findings in 175 of 190 patients (92 1%). Conclusion MCV and F wave parameters are sensitive measures for detection of DPN. Among these parameters, FwPL, F MIPL from all the four nerves are the most sensitive. To improve diagnostic accuracy, all the MCV and F wave parameters recorded should be considered.