OBJECTIVE: To explore ABO blood group distribution and clinical characteristics in patients with COVID-19. METHODS: The clinical data of 187 patients with COVID-19 seen between January 20, 2020 and March 5, 2020 at the First Hospital of Changsha were retrospectively analyzed. The differences in the ABO blood group distribution between COVID-19 patients and the control group (1991 cases) were analyzed. The relationship between blood type and clinical characteristics was analyzed. RESULTS: Of the 187 patients with COVID-19, 69 had type A (36.90%), 63 had type B (33.69%), 41 had type O (21.92%), and 14 had type AB blood (7.49%). The proportion of patients with type A blood in the COVID-19 group was significantly higher than that in the control group (36.90% vs. 27.47%, P = 0.006), while the proportion of patients with type O blood in the COVID-19 group was significantly lower than that in the control group (21.92% vs. 30.19%, P = 0.018). The risk of COVID-19 was higher for individuals with blood group A than for those with blood group O (OR = 1.849, 95% CI = 1.228-2.768, P = 0.003). The risk of COVID-19 was higher for patients with blood group A than for those with a blood group other than A (OR = 1.544, 95% CI = 1.122-2.104, P = 0.006). Patients with blood group O had a lower risk of COVID-19 than non-O blood group patients (OR = 0.649, 95% CI = 0.457-0.927, P = 0.018). The ABO blood group distribution was related to COVID-19 status. CONCLUSIONS: Patients with blood group A had an increased risk for infection with SARS-CoV-2, whereas blood group O was associated with a decreased risk, indicating that certain ABO blood groups were correlated with SARS-CoV-2 susceptibility. Blood type was related to some clinical characteristics of patients with COVID-19.