The corona virus disease of 2019 (Covid-19) is a deadly viral infection rampaging the world since 2019. Health practitioners have identified co-morbidities as one of the factors contributing to the severity of the disease among patients, with diabetes being one of the leading co-morbid. A systematic search was performed on PubMed, Google Scholar and Science hub databases to obtain articles that have addressed the link between diabetes and severity in Covid-19 infection. A meta-analysis to obtain a pooled effect of the effect of diabetes on the severity of Covid-19 (odd ratio OR) was calculated using R programming language and a funnel plot to check for publication bias was also plotted. Twelve studies with 3,180,125 diabetic patients with confirmed cases of Covid-19 (out of 61,820,553 confirmed Covid-19 participants) were included for the meta-analysis. The obtained pooled effect of diabetes on the severity of Covid-19 infection was (OR=1.47; 95% CI 1.33-1.63). From the meta-analysis results; Age, diabetic complications and drugs for the treatment of diabetes were identified as possible co-factors to the diabetic effect on Covid-19 infection, as diabetes was seen to be significantly related to its severity but not mortality. It is therefore very important for diabetic patients to adhere strictly to every laid down regulation regarding Covid-19. More clinical research on alternative diabetic therapy is needed as this will reduce the negative effect of insulin usage.