ObjectivesTo systematically review the efficacy and safety of hydroxychloroquine (HCQ) and chloroquine (CQ) for oral lichen planus (OLP).MethodsPubMed, The Cochrane Library, Web of Science, CNKI, CBM, VIP and WanFang Data databases were electronically searched to collect randomized controlled trials (RCTs) of HCQ and CQ for OLP from inception to September, 2018. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies, then, meta-analysis was performed by using RevMan 5.3 software.ResultsA total of 10 RCTs involving 726 patients were included. The results of meta-analysis showed that: HCQ or CQ were more effective than placebos (P<0.05). Nevertheless, they were inferior to oral traditional Chinese medicine (RR=0.75, 95%CI 0.69 to 0.82, P<0.000 01). In addition, the ratio of CD4+/CD8+ T cell increased significantly in peripheral blood of OLP patients after treatment with HCQ or CQ (MD=–0.28, 95%CI –0.44 to –0.13, P=0.000 3). The incidences of adverse reaction of HCQ or CQ were higher than orally traditional Chinese medicine (RR=11.80, 95%CI 4.85 to 28.68, P<0.000 01), and the difference was statistically significant.ConclusionsCurrent evidence shows that the efficacy of HCQ or CQ for OLP were significantly superior to placebo, while inferior to orally traditional Chinese medicine. The possible therapeutic mechanism of HCQ or CQ for OLP may be related to the regulation of the ratio of CD4+/CD8+ T cells and cellular immunity of OLP patients. Due to limited quality and quantity of the included studies, more high quality studies are required to verify above conclusion.