Background: Previous studies showed that diabetes was a common comorbidity of COVID-19, but the effects of diabetes or anti-diabetic drugs on the mortality of COVID-19 have not been well described. To investigate the outcome of different status (with or without comorbidity) and anti-diabetic medication before admission of diabetic patients after SARS-CoV-2 infected, we collected clinical data of COVID-19 patients from Hubei Province and compared between diabetes and non-diabetes.Methods: In this multicenter and retrospective study, we enrolled 1,422 cases of consecutive hospitalized patients from January 21, 2020 to March 25, 2020 at six hospitals in Hubei Province, China. The primary endpoint was in-hospital mortality.Results: Diabetes patients were 10-years older than non-diabetes (p<0.001), had higher prevalence of comorbidities such as hypertension (p<0.001), coronary heart disease (p<0.001), cerebrovascular disease (CVD) (p<0.001), chronic kidney disease (CKD) (p=0.007). The incidence of mortality (p=0.003) were more prevalent among the diabetes group. Further analysis revealed that diabetes patients who took alpha-glucosidase inhibitor (AGI) had lower mortality rate(p<0.01). Multivariable Cox regression showed that male sex, hypertension, CKD, CVD, age were risk factors for the mortality of COVID-19. Survival curve revealed that, compared with diabetes only group, the mortality was increased in diabetes with comorbidities (p=0.009), but had no significant difference in the non-comorbidity group, p=0.59).Conclusions: Patients with diabetes had worse outcome when suffered with COVID-19, however, it was not associated with diabetes itself but the comorbidities. Furthermore, the administration of AGI could reduce the risk of death in patients with diabetes.