Abstract: Objective: To explore the difference in axon regeneration distance,Schwann cells,visualization of blood vessels and macrophages of two kinds of allografted acellular basal lamina tubes pretreated respectively by chemical extraction procedure and freeze-thawed procedure.Methods: Thirty six Wistar rats were divided randomly into two groups,chemical extracted nerve(CEN) group and freeze-thawed nerve(FTN) group,which were allografted by two kinds of acellular basal lamina tubes of Sprague-Dawley rats' sciatic nerves.At day 8,13 and 23 after the operation,the grafts,together with a proximal and distal nerve segment,were removed and were observed by histochemistry and immunohistochemistry to reveal the morphological difference.Results: CEN was better than FTN at supporting the outgrowth of axon,migration of Schwann cells,visualization of blood vessels and macrophages.Conclusions: The chemical extraction procedure can offer a better solution to the repair of a gap in the continuity of the peripheral nerve.