Aim To develop a new animal model for the investigation of adventitial function in atherosclerosis.Methods One carotid artery adventitia of rabbit with 2 mg/mL typeII collagenase was digested,then adventitia with microforceps was removed,and the contralateral carotid artery was used as control.HE staining and immunohistochemistry were performed to assure adventitia was removed,and to assess intimal change after adventitial removal.Results It is feasible to remove vascular adventitia with collagenase digestion and mechanical dissection.Removal of adventitia of rabbit carotid artery induced neointima development in 2 weeks.Cells in neointima were secreating smooth muscle cells.The other sides were normal.Conclusions The method we used to remove artery adventitia is effective.Normal adventitia is necessary for normal vessel structure.