Objective To investigate effect of autologous periosteum transplantation in the repair of anterior cruciate ligament (ACL) injury.Methods Transected ACL injury was induced in 24 white rabbits randomly allocated to receive autologous periosteum transplantation with suture fixation (study group,n =12),isolated suture fixation (control group,n =12),and arthrotomy (blank group,n =3).Gross observation of ACL repair was performed and degeneration of knee joint was evaluated using the Markin score.ACL pathology,collagen fiber formation and insertion degenerative changes were histologically investigated using the HE staining,Masson staining and Picric-Sirius red staining.Results Twelve weeks after the operation,gross observation showed ligamentous continuity and minor joint degeneration in study group.Opposite results were seen in control group.Markin joint degeneration score calculated 7.2 ± 1.6 in study group,12.4 ± 1.8 in control group and 0.6 ± 0.4 in blank group,with significant differences between groups (P ＜ 0.05).Using the HE and Masson staining in study group,rich collagen fibers and microvessel as well as cell infiltration were found in wound tissue and the ligaments were covered with synovial membrane.However,wound tissue did not heal in control group,leaving ligament remnants with loosely disorganized fibers and rich microvessel as well as cell infiltration.And only the residual stump was wrapped with synovial membrane.Using the HE and Picric-Sirius red staining,the typical four-layer structure of ACL insertion remained intact in study group,whereas in control group the layer structure of ACL insertion in control group became disorganized and the tidemark of enthesis almost disappeared.Conclusion Autologous periosteum transplantation is effective to improve the injury healing and mitigate the degeneration of joint.