To assess regenerative capacities of chitosan-nanoselenium conduit on transected sciatic nerve in diabetic rats. Methods: A 10-mm sciatic nerve defect was bridged using a chitosan-nanoselenium conduit filled with phosphate buffered saline. In chitosan group, the chitosan conduit was filled with phosphate buffered saline solution. In sham-operated group, sciatic nerve was exposed and closed. In transected group, right sciatic nerve was transected and nerve cut ends were fixed in the adjacent muscle. The regenerated fibers were studied within 12 weeks after surgery. Results: The behavioral and functional and electrophysiological tests confirmed faster recovery of the regenerated axons in chitosan-nanoselenium conduit group compared to chitosan group (p=0.001). The mean ratios of gastrocnemius muscles weight were measured. There was statistically significant difference between the muscle weight ratios of chitosan-nanoselenium conduit and chitosan groups (p=0.001). Morphometric indices of regenerated fibers showed number and diameter of the myelinated fibers were significantly higher in chitosan-nanoselenium conduit group than in chitosan group. Conclusion: chitosan-nanoselenium conduit resulted in acceleration of functional recovery and quantitative morphometric indices of sciatic nerve.