Aims: To identify possible risk factors of hospitalisation in patients with diabetes (DM) and 2019 novel coronavirus disease (COVID-19), to establish the prevalence of DM among infected patients and that of DM in patients requiring hospitalisation. Research design and methods: Between March-May 2020, 1202 consecutive subjects in the healthcare area of Santiago de Compostela and Barbanza (Galicia, Spain) were diagnosed with COVID- 19, among whom 136 patients with DM were identified. Demographic data, DM characteristics and complications during hospitalisation were collected and analysed. Results: The prevalence of DM among COVID-19 infected subjects was 11.3%. This ascended to 21.7% in inpatients, while only 8.1% of outpatients had DM (p<0.0001). Higher levels of glycated haemoglobin significantly increased the risk of hospitalisation (OR: 1.57;95% CI: 1.03-2.41, p=0.037), with small differences making the difference between inpatients and outpatients (7.3 +/- 1.3% vs 6.8 +/- 0.9% [56 +/- 14 vs 51 +/- 10 mmol/mol], respectively, p=0.009). Obesity (BMI = 30 kg/m2) was the only comorbidity associated to hospitalization (OR: 2.94;95% CI: 1.17-7.30, p=0.021). There were no differences in the type and duration of DM, the type of glucose-lowering drugs, or in the presence of micro/macrovascular complications. Conclusion: DM does not increase the risk of suffering from COVID-19, but it can worsen the outcome, raising the hospitalisation rate. Thus, obesity and worse chronic glycaemic control, even with small variations, are independent and determining factors for severe forms which require hospitalisation.