Objective To explore the diagnostic value of tibial nerve short-latency somatosensory evoked potential( SLSEP)and F wave in proximal diabetic neuropathy.Methods Excluding stroke,waist cervical vertebra sickness and nerve-muscle diseases caused by other diseases,there were clinical signs of neuropathy but normal nerve conduction EMG(Ⅰ group)32 cases,there weren't clinical signs of neuropathy normal nerve conduction EMG(Ⅱ group)30 cases and abnormal nerve conduction EMG(Ⅲgroup)30 cases.Tibial nerve SLSEP and F wave were measured in 92 patients and 30 normal persons.Results The highest whole abnormality rate of tibial nerve SLSEP's and F wave's all parameters was the sub-group (there were neuropathy symptom lower limbs n=43)of Ⅰ group(97.7% (42/43)).In Ⅰ group Fdur,NI3CV,N24CV, N13-N24CV,N9-N24CV were significantly different from the control group (q value:5.887 and 6.780,-4.568 and-5.062,-6.799 and -6.905,-5.978 and -5.609,-5.433 and -5.190, P＜0.01);The abnormality rate of Fdur and N13-N24CV (25.0%(15/60),23.3% (14/60))in Ⅱgroup were significantly different from the control group (0,1.7%(1/60))also (x2=17.143,12.876, both P=0.0050).In Ⅲ group,except for N9-N24CV,N13 and N24 wave amplitude other parameters'abnormality rates were significantly different from the control group,and the abnormality rate of N9CV was the highest (76.7%(46/60)).Conclusion(1)SLSEP can provide information of proximal sensory nerve segment.(2)SLSEP and F wave can improve the diagnosis rate of proximal diabetic neuropathy,and the diagnostic value is particularly significant to the diabetes patients who have clinical signs of neuropathy but normal nerve conduction EMG.