Abstract:Objective To evaluate the status of cognitive function objectively by using the somatosensory evoked potential technology. Methods Recorded the relevant data of the somatosensory evoked potential test in the normal group, non-cognitive impairment group and MCI group, and 30 cases in each group. All data were analyzed statistically by SPSS 19.0 software. Results The results showed that the latent period of the peripheral nerve evoked potential and subcortical potential had no statistical significance in the three groups (P?>?0.05). The latent period of the cortical potential and the conduction time of central nerve in MCI group had statistical significance compared with the other two groups (P?0.05). The latent period of P60, N75 in the non-cognitive impairment group had statistical significance compared with the normal group (P?0.05), but no statistical difference of the conduction time of central nerve (P?>?0.05). Conclusion The research shows that the cortical potential of SEP was more sensitive to the evaluation of cognitive function and better than the scales. The cortical potential of SEP can be used to assess subclinical period in MCI. The cortex potential of the posterior tibial nerve had more advantages than the SEP of median nerve of subclinical stage and early evaluation of MCI.