Background: The role of the ABO blood group goes beyond immunohematology as there is accumulating evidence on its association with type 2 diabetes mellitus. However, findings regarding the relation have been contradictory and there is a need to determine the validity of claims. Objective: Evaluate the susceptibility of the ABO blood groups to type 2 diabetes mellitus. Method: The research design is a meta-analysis. An extensive search was done in PubMed, ScienceDirect, ResearchGate, and Google Scholar. Heterogeneity was determined through Cochran’s Q test and I2 index. Random-effects model was used to measure the risk ratio and confidence intervals. Evaluation of publication bias was done using the funnel plot method; further supported by Egger’s linear regression test and Begg’s test. Results: The relative susceptibility of ABO blood groups to type 2 diabetes mellitus differs for blood type A (Relative risk [RR] = 1.05, 95% CI, 0.93 to 1.18), blood type B (RR = 1.03, 95% CI, 0.91 to 1.18), blood type AB (RR = 1.25, 95% CI, 0.78 to 1.99), and blood type O (RR = 1.11, 95% CI, 0.82 to 1.48). The highest risk of acquiring the disease was seen in type AB individuals, while the lowest risk was seen in type B individuals. Conclusion: A significant association was found between ABO blood groups and type 2 diabetes mellitus. ABO phenotype can therefore be considered a possible risk factor or potential genetic determinant of the disease, which can be used to improve diagnosis and treatment.