© Copyright © 2019 Taylor & Francis Group, LLC.Introduction: We investigated the possible beneficial effect of dimethylsulfoxide (DMSO) on peripheral nerve repair in rats. Methods: Seventy rats were divided into four groups: control, sham, DMSO-L, and DMSO-IP. Except in the control group, nerve repair was done at the right sciatic nerve. DMSO was administered locally and intraperitoneally for 12 weeks to the DMSO-L and DMSO-IP groups, respectively. No therapeutic agent was administered to the other groups. Nerve regeneration was assessed by behavioral, electrophysiological, histopathological, and immunohistochemical tests. Results: With the exception of S-100 protein expression, all results indicate that DMSO has a beneficial effect on peripheral nerve regeneration. Functional nerve recovery was notably more evident in the DMSO-L than in the DMSO-IP group. Under macroscopic examination, nerve scores of the regeneration area in the DMSO-L group was also better than in the others. Discussion: We believe that DMSO can improve peripheral nerve regeneration in rats.