Objective: To investigate the association between the ABO blood group and the COVID-19 susceptibility. Material & Methods: The study is a retrospective cohort study. It included all hospitalized confirmed COVID-19 patients in Qatif central hospital, Eastern province, Saudi Arabia. Results: Our sample consists of 72 patients, we found a percentage distribution of 23.62%, 33.33%, 9.72%, and 33.33% for blood groups A, B, AB and O, respectively. Our results showed significantly increased risk for AB blood groups and significantly lower risk for the O blood group. Although there was a higher percentage distribution of the B blood group among COVID-19 patients as compared to the blood donors’ groups, this difference did not reach statistical significance. Conclusion: patients with AB blood group have higher susceptibility while patients with O blood group have lower susceptibility to COVID-19 infection. Our study has limitations and further studies are needed.