Abstract: Objective To study the repair of urethral defect in rats with acellular urethra in order to find its ideal methods and materials. Methods Twenty urethras were taken from SD rats and cut into 1cm-long segments.Their cell components were isolated with chemical acellular methods with their extracellular matrix preserved for the preparation of acellular urethra.A 1cm-long segment defect model of urethra from 10 Wistar rats was established.Urethral defect in SD rats was repaired with acellular allo-urethra transplantation.Uriodynamics was detected 3 weeks after operation with VG staining.Ten Wistar rats underwent allo-transplantation and another 10 Wistar rats that underwent auto-transplantation served as controls. Results No difference was observed in urethral pressure,maximal bladder volume and residual urine volume between experimental and control groups（P＞0.05）.VG staining showed that the broken end of anastomotic stoma was stained red in experimental group.The muscle fibers were orderly arranged and well distributed.The regenerated muscle fibers grew into the distal urethra.The muscle fibers were also orderly arranged and well distributed in control group with no regenerated muscle fibers grown into the distal urethra. Conclusion Acellular allo-urethra can repair the urethral defect in higher mammals.