Objective:To study the predictive factors of effect on idiopathic thrombocytopenic purpura (ITP) after laparoscopic splenectomy(LS). Methods:The clinical records of 25 patients with ITP treated by LS during Jan.2000 to Oct.2007 were retrospectively analyzed. Results:There was no mortality or severe complication during LS. All these patients were successfully operated by LS,including 2 cases operated by LS assisted with short incision. The median follow-up was 3.5 years(1~7years),The postoprative remission rate was 80%(20/25),and the 2-year remission rate was 72%(18/25),including 2 remission patients who had severe anemia from a bleeding gastric ulcer and side effects of high dose and long-term corticosteroid treatment before LS.Multivariated analyses showed younger patients(≤50 y) responded more positively than older patients(>50 y) to LS(P<0.05).Likewise, platelet counts on 7th postoperative day coincided with those at 2-year follow up. Average platelet counts in remission and no remission patients with ITP were 307×109/L and 103×109/L on 7th postoperative day respectively(P<0.05). Conclusions:LS is a safe and effective therapy for patient with ITP. Young Patients (≤50 y) with need high dose of corticosteroids or are resistant to corticosteroids should undergo LS.Age at surgery (≤50 y) and platelet counts on 7th postoperative day might predict the effect of laparoscopic splenectomy.