Ｏｂｊｅｃｔｉｖｅ　Systematically evaluation the effect of ulinastatin on postoperative cognitive dysfunction(POCD) in elderly patients after receiving noncardiac surgery under general anesthesia. 　Methods　The randomized controlled trials(RCT) about influence of Ulinastatin on POCD of elderly patients after receiving noncardiac surgeries with general anesthesia were searched in PubMed, Embase, Cochrane, CNKI, VIP and Wanfang data library till March, 2016. Two reviewers independently screened literature according to the inclusion and exclusion criteria, extracted data and assessed the risk of bias of included studies. Then, RevMan 5.3 software was used for Meta analysis.　Results　A total of 10 RCT were included. The results of Meta analysis showed that: ① compared with the control group, Ulinastatin reduced the incidence of postoperative cognitive dysfunction on the first day [odds ratio(OR)=0.32, 95%CI: 0.16-0.62, P<0.05), on the third day(OR=0.28, 95%CI: 0.14-0.58, P<0.05) and on the seventh day(OR=0.25, 95%CI: 0.14-0.46, P<0.05). ② Compared with the control group, Ulinastatin decreased the expression level of inflammatory factor IL-6[after 24 h: standardized mean difference(SMD)=-2.93, 95%CI: -4.43- -1.44, P<0.05, after 3 d: SMD=-1.80, 95%CI: -2.91- -0.69, P<0.05]. Ulinastatin also reduced the expression of S100β(instant: SMD=-1.75, 95%CI: -2.90- -0.61, P<0.05, after 24 h: SMD=-2.43, 95%CI: -2.91- -1.95, P<0.05).　Conclusions　Ulinastatin can effectively reduce the incidence of POCD in elderly patients after receiving noncardiac surgeries under general anesthesia and decreased the expression of inflammatory factor IL-6 and S100β.