Background and objectives Several large scale cohort studies suggest that BCG vaccination in early childhood may reduce the risk of allergic disease, but the consequences remain controversial. The objective of this study was to investigate the associations between early childhood BCG vaccination and the risk of developing allergic disease. Methods Eligible studies published on PubMed, EMBASE and Cochrane Central Register of Controlled Trials were systematically sourced from inception to April 2020. Large-scale cohort or cross-sectional studies with 100 participants or more, focusing on the association between BCG vaccine and allergic disease including eczema, asthma and, rhinitis were included. An assessment was undertaken by two independent investigators looking at methods, interventions, outcomes, and study quality. Odds Ratio (OR) with 95% confidence interval (CI) were calculated. Results Our study included 13 large-scale studies involving a total of 260,029 participants. Our quantitative analysis found that administering BCG vaccine in early childhood significantly reduced the risk of developing asthma (OR 0.74, 95%CI 0.61 to 0.91), but there was no association between early childhood BCG vaccination and the risk of developing eczema (OR 0.87, 95%CI 0.68 to 1.11) or rhinitis. (OR 1.03, 95%CI 0.87 to 1.22). The effect of BCG vaccination with asthma was evident especially in European countries (OR 0.59, 95%CI 0.40 to 0.88) and American countries (OR 0.90, 95%CI 0.82 to 0.98) Conclusions Use of BCG vaccination in early childhood may be associated with a reduced risk of allergic disease, especially in European and American countries.