Objective To study the clinical effects of shortening the drainage time for patients with dural tears after posterior spinal sur -gery.Methods A total of 120 patients with dural tears after posterior spinal surgery were randomly divided into study group and control group,60 patients in each group .Patients in control group had wound drainage tubes removed after 5 days and patients in study group had wound drainage tubes removed after 3 days.The disappearance time of leakage ,incision healing time and complication rate were compared between two groups.Results The disappearance time of leakage in study group was (13.7 ±3.8)days which was significantly less than (20.0 ±5.1)days in control group(P<0.05).The incision healing time in study group was (22.7 ±4.9)days which has no significant difference with (23.9 ± 5.7)days in control group.The postoperative infection rate was 3.3%(2/60) which was significantly less than 20.0%(12/60) in control group(P<0.01).Conclusion Shortening drainage time can decrease the disappearance time of leakage and postoperative infection rate .