Objective： In order to summarize the clinical research on regulatory effect of Lactobacillus reuteri on immunity in recent decades through meta-analysis， and to explore the regulatory effect of L. reuteri on the immune function of organism. Methods： Literature searches were conducted through 5 databases including Medline， SCI， Wan-Fang data， China National Knowledge Infrastructure and Chinese Biological Medical databases. Review Manager version 5.3 was used to organize data and statistical analysis of included randomized controlled trials. A P value less than 0.05 in confidence interval method was considered statistically significant. Results： 6 references and 13 RCTs were included in this work after researching. The number of subjects included in the meta-analysis was 740， with 362 for the control group and 378 for the probiotics. Mean differences observed between probiotic-receivers and control at 95% confidence interval： TNF-α，-3.09 pg/mL （[-4.17，-2.02]； P<0.0001）； IL-6，-4.49 pg/mL （[-7.08，-1.90]； P<0.0001）； IL-1β，-8.72 pg/mL （[-12.53，-4.92]；P<0.0001）； IL-8， -69.71 pg/mL （[-103.84， -35.58]； P<0.0001）. Conclusion： L. reuteri has a certain regulatory effect on the subjects' immunity.