Objective: To systematically review the effects of mechanical tongue cleaning on halitosis. Methods: Searching and collecting the RCTs about treatment combine with mechanical tongue cleaning from inception to May 2017 in the databases, like CNKI, VIP, WanFang Data, PubMed, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), The Cochrane Library, Web of Science. Two reviewers screened the literatures according to inclusion and excluding criteria, extracted the data independenly, assessed bias risks. In case of disagreement, the discussion shall be settled by the third reviewer. Meta-analysis was conducted by RevMan 5.3. Results: A total of 4 RCTs with 185 volunteers were included. The results of Meta-analysis showed that treatment combine with mechanical tongue cleaning has an advantage over the control group in the levels of Winkel Tongue Coating Index (WTCI) [MD = 2.15, 95%CI(0.93,3.36), = 0.0006], Organoleptic Assessment (ORG) [MD = -0.71, 95%CI(-0.95,-0.48), ＜0.00001], but no significant differences between two groups in Volatile Sulphur Compounds (VSCs) [SMD = -1.13, 95%CI(-2.91,0.65), = 0.21], Bleeding On Probing (BOP) [MD = -1.01, 95%CI(-7.05,5.03), = 0.74]. Conclusion: Treatment combined with mechanical tongue cleaning could reduce risks of halitosis and WTCI.