ObjectiveTo systematically review the association between Helicobacter pylori (HP) infection and Parkinson's disease (PD). MethodsPubMed, EMbase, The Cochrane Library, CNKI, VIP and WanFang Data databases were electronically searched to collect case-control studies on the association between HP and PD from January 2000 to July 2021. Two reviewers independently screened literature, extracted data, and assessed the risk of bias of included studies. Meta-analysis was then performed using RevMan 5.3 software. ResultsA total of 16 case-control studies involving 2 790 subjects were included. The results of meta-analysis showed that the HP infection rate was higher in PD patients than that in healthy patients (OR=1.87, 95%CI 1.38 to 2.54, P<0.000 1). The results of subgroup analysis showed that the infection rate of HP in PD group in Asia and Africa region was significantly higher than that in control group, but not in Europe region. Breath tests and other detection methods were used to detect HP infection, and the HP infection rate in PD group was significantly higher than that in the healthy control group. However, there was no significant difference in HP infection between the two groups by ELISA. UPDRS Ⅲ score of PD patients with HP infection was significantly higher than that of PD patients without HP infection. ConclusionsCurrent evidence shows that PD patients have a higher HP infection rate than the normal population, and the rates are affected by regions and HP detection methods. In addition, HP infection can aggravate the motor symptoms and motor complications of PD patients. Due to limited quality and quantity of included studies, more high-quality studies are required to verify the above conclusions.