ObjectiveTo systematically review the curative effect and safety of compound realgar and natural indigo tablet (CRNIT) therapy in acute promyelocytic leukemia (APL). MethodsThe clinical data of randomized trials on SinoMed, CNKI, VIP,WANFANG DATA,CBA, PubMed, MEDLINE, EMBASE, the Cochrane Library were searched by internet,in addition to manual retrieval and collecting all published literatures randomized controlled trials (RCT) about CRNIT therapy in APL home and abroad.Retrieval line was up to March 2011. According to the inclusion criteria and exclusion criteria, screening all literatures and evaluating their qualities. The rate of complete remission (CR), time to CR, recurrence rate, mortality, rate of adverse reaction and so on were used as evaluation indicators for meta-analysis by RevMan 5.1.Results Data from six RCTs involving 391 APL patients,including 2 RCTs about comparison of CRNIT and Arsenic Trioxide (ATO), 4 RCTs about comparison of CRNIT and all-trans retinoic acid (ATRA) (including adding 1 RCT about comparison of CRNIT + ATRA and ATRA). Time to CR: CRNIT was longer than ATRA and ATO (WMD = 3.14, 95 ％ CI 0.99-5.29, P= 0.004). Headache incidence: CRNIT was lower than ATRA (OR = 0.10, 95 ％ CI 0.02-0.45, P = 0.003). 5-year disease-free survival rate: CRNIT was better than ATRA (OR = 7.22, 95 ％ CI 1.40-37.25, P = 0.02). There were no statistical significance in the rest of the Meta-analysis results.ConclusionThe time to CR of CRNIT is longer than that of ATRA and ATO.The short-term effect of CRNIT is similar to that of ATRA and ATO.The 5-year disease-free survival rate of CRNIRT may be higher than that of ATRA.