Background Coronavirus disease 2019 (COVID-19) emerged in December 2019 and has spread globally. Diabetics are at increased risk of infections caused by a variety of pathogens including viruses. The present research aims to describe clinical characteristics and outcomes of COVID-19 patients with diabetes. Methods A retrospective multicenter study of COVID-19 patients with diabetes was conducted in four hospitals in Wuhan, Shanghai, and Anhui Province. Reverse transcription polymerase chain reaction or next-generation sequencing was carried out to confirm the existence of severe acute respiratory syndrome coronavirus 2 from respiratory specimens. Results A total of 54 diabetics (10.36%) were recruited from among 521 COVID-19 patients, with a median age of 63 (interquartile range, 52-70) years. Among them, 51 had been previously diagnosed with diabetes and 3 had been newly diagnosed based on glycosylated hemoglobin over 6.5%. For COVID-19, 47 of the 54 patients had an exposure history. Fever (47/54, 87.04%), dry cough (36/54, 66.67%), and expectoration (21/53, 39.62%) were among the top three symptoms. Lung infiltration was bilateral (46/52, 88.46%) and multilobe (47/52, 90.38%), and ground-glass opacity (36/37, 97.30%) was the most common pattern in radiological images. Moreover, COVID-19 patients with diabetes were prone to be classified as severe or critical cases (46.30%, 25/54) and had complications such as acute lung injury, acute respiratory distress syndrome, and acute kidney injury. The proportions of intensive care unit (ICU) admissions and deaths among the COVID-19 diabetics were 14.81% (8/54) and 12.96% (7/54), respectively. Conclusions With older age, diabetics diagnosed as having COVID-19 were prone to develop into severe cases and exhibited a high rate of ICU admission and mortality.