AIM: To compare the efficacy and safety of biological agents for the treatment of active ulcerative colitis(UC).METHODS: PubMed, MEDLINE, EMBASE and the Cochrane library were searched to screen relevant articles from January 1996 to August 2014. The mixedtreatment comparison meta-analysis within a Bayesian framework was performed using WinBUGS14 software.The proportions of patients reaching clinical response,clinical remission and mucosal healing in induction and maintenance phases were analyzed as efficacy indicators. Serious adverse events in maintenance phase were analyzed as safety indicators.RESULTS: The meta-analysis results showed that biological agents achieved better clinical response,clinical remission and mucosal healing than placebo.Indirect comparison indicated that in induction phase,infliximab was more effective than adalimumab in inducing clinical response(OR = 0.41, 95%CI:0.29-0.57), clinical remission(OR = 0.33, 95%CI:0.19-0.56) and mucosal healing(OR = 0.33, 95%CI:0.19-0.56), and golimumab in inducing clinical response(OR = 0.66, 95%CI: 0.39-2.33) and mucosal healing(OR = 2.15, 95%CI: 1.18-4.22). No significant difference was found between placebo and biological agents regarding their safety.CONCLUSION: All biological agents were superior to placebo for UC treatment in both induction and maintenance phases with a similar safety profile, and infliximab had a better clinical effect than the other biological agents. AIM: To compare the efficacy and safety of biological agents for the treatment of active ulcerative colitis (UC). METHODS: PubMed, MEDLINE, EMBASE and the Cochrane Library were searched to screen relevant articles from January 1996 to August 2014. The mixedtreatment comparison meta -analysis within a Bayesian framework was performed using WinBUGS14 software. proport proport of patients reaching clinical response, clinical remission and mucosal healing in induction and maintenance phases were analyzed as efficacy indicators. Serious adverse events in maintenance phase were analyzed as safety indicators .RESULTS: The meta-analysis results showed that biological agents achieved better clinical response, clinical remission and mucosal healing than placebo. Indirect comparable indicated that in induction phase, infliximab was more effective than adalimumab in inducing clinical response (OR = 0.41, 95% CI: 0.29 -0.57), clinical remission (OR = 0.33, 95% CI: 0.19-0.56) and mucosal healing (OR = 0.33, 95% CI: 19-0.56), and golimumab in inducing clinical response (OR = 0.66, 95% CI: 0.39-2.33) and mucosal healing (OR = 2.15, 95% CI: 1.18-4.22). No significant difference was found between placebo and biological agents regarding their safety. CONCLUSION: All biological agents were superior to placebo for UC treatment in both induction and maintenance phases with similar safety profile, and infliximab had a better clinical effect than the other biological agents.