Introduction and Objectives. Treatments to eradicate H. pylori have lost effectiveness due to the appearance of resistance to antibiotics. The usefulness of probiotics added to triple and quadruple therapies is controversial. Our goal was to do some research on the effectiveness of probiotics by adding them to eradication therapies. Materials and Methods: We investigated databases to identify randomized clinical experiments on the treatment of H. pylori from January 2010 to May 2020 that included probiotics compared to placebo or non-intervention. The effect was estimated with Odds Ratio (OR), heterogeneity with I2 and Chi2. The raw analyses were presented as relative risk (RR). Results: Twelve randomized clinical trials (RCTs) involving 1,091 patients were identified. Nine RCTs were conducted with triple therapy, two with quadruple therapy and one with triple and quadruple therapy. In triple therapies, probiotics were more effective than placebo 79.4% vs 71.1%, (OR = 1.42; 95% CI = 1.05-0.09; I2 = 0%). In quadruple therapies, the effectiveness did not increase. The most widely used probiotic was Lactobacillus reuteri, with rates of 77.9% (95% CI = 70.5-84.19) versus 66.8% (95% CI = 58.8-74.2). Probiotics decreased adverse effects in triple (OR = 0.50; 95% CI = 0.28-0.90); I2=0%) and quadruple (OR= 0.26; 95% CI = 0.09-0.74; I2=0%) therapies. Conclusion: Probiotics improve the effectiveness of triple therapies by 8.5%, but the final success remains poor (<90%). It does not increase the effectiveness of quadruple therapies. They decrease adverse effects significantly. No further studies with probiotics in triple therapies are justified. Keywords: Helicobacter pylori, probiotics, eradication, adverse effects