Background ABO blood type associated with differentiated onset of infectious diseases. Aims/Objective To investigate whether people with different blood types were vulnerable in developing chronic otitis media (CSOM) and if the risk and protective factors varied among them. Material and methods The study was a case-control study that included 206 participants in the case group and 210 in the control group. Stratified analysis for blood type was adopted. Results Patients with different blood types were insignificantly different in the incidence of CSOM. Upper respiratory tract infection (URTI, OR = 21.81, 95% CI: 4.80–99.06), socioeconomic status (OR = 3.02, 95% CI: 1.35–6.74), and were risk factors in blood type A. In blood type B, smoking and urban residence were risk factors. The OR (95% CI) were 11.42 (2.77–47.08), and 0.14 (0.03–0.65). Urban residence, BMI and blood calcium increase, male gender were protective factors for different blood types. Conclusions and significance Our study identified the risk and protective factors for CSOM among different blood types. The findings might provide new insights into taking precautions against CSOM in people of different blood types.