Aim: The aim of this study was to investigate the ABO and Rh blood group distribution and clinical characteristics in patients with Covid-19. Materials and Methods: The clinical characteristics and blood groups of 1667 patients who were hospitalized due to Covid-19 (with a positive PCR test) between 16 March and 10 July were reviewed cross-sectionally.. Results: When blood groups of patients diagnosed with Covid-19 and control group were compared, it was observed that there was increase in the number of Covid-19 patients with blood groups A and AB, decrease in the number of Covid-19 patients with blood group O, a statistically significant increase in the number of individuals with blood group A in Covid-19 patients compared to healthy individuals, and almost significant increase in the number of Covid-19 patients with blood group AB and a very significant decrease in the number of Covid-19 patients with blood group O. Conclusion: Our study has found that having blood group O may be protective, that blood group A may have greater susceptibility to the disease, but this does not affect the course of the disease and is not associated with mortality.