Diarrhea is a major infectious cause of childhood morbidity and mortality worldwide. In clinical trials, GG ATCC 53013 (LGG) has been used to treat diarrhea. However, recent randomized controlled trials (RCTs) found no evidence of a beneficial effect of LGG treatment. To evaluate the efficacy of LGG in treating acute diarrhea in children. The EMBASE, MEDLINE, PubMed, Web of Science databases, and the Cochrane Central Register of Controlled Trials were searched up to April 2019 for meta-analyses and RCTs. The Cochrane Review Manager was used to analyze the relevant data. Nineteen RCTs met the inclusion criteria and showed that compared with the control group, LGG administration notably reduced the diarrhea duration mean difference (MD) -24.02 h, 95% confidence interval (CI) (-36.58, -11.45). More effective results were detected at a high dose ≥ 10 CFU per day MD -22.56 h, 95%CI (-36.41, -8.72) a lower dose. A similar reduction was found in Asian and European patients MD -24.42 h, 95%CI (-47.01, -1.82); MD -32.02 h, 95%CI (-49.26, -14.79), respectively. A reduced duration of diarrhea was confirmed in LGG participants with diarrhea for less than 3 d at enrollment MD -15.83 h, 95%CI (-20.68, -10.98). High-dose LGG effectively reduced the duration of rotavirus-induced diarrhea MD -31.05 h, 95%CI (-50.31, -11.80) and the stool number per day MD -1.08, 95%CI (-1.87, -0.28). High-dose LGG therapy reduces the duration of diarrhea and the stool number per day. Intervention at the early stage is recommended. Future trials are expected to verify the effectiveness of LGG treatment.