Diabetes mellitus, and its complications and comorbidities form a major component of emerging non-communicable diseases (NCDs) in developing countries where they coexist with traditional infectious diseases. The potential cost of optimum management of complications arising from diabetes and other NCDs adds an additional burden to the economy of African countries already living in poverty, with limited affordability of treatment. We describe a prospective cross-sectional study carried out in Kigali University Teaching Hospital, Rwanda, between October 2008 and May 2010, to investigate the clinical patterns and complications profile of diabetic patients attending the Department of Internal Medicine. The study involved 294 patients (65% females, 40% of patients aged below 45 years). Co-morbidity with hypertension, overweight and dyslipidemia was found in 31%, 33%, and 28%, respectively. The mean diabetes duration was 6±6 years (mean ± SD). Microvascular complications were common: neuropathy (53%), retinopathy (23%), and nephropathy (20%). Macrovascular complications were less frequent: cerebrovascular disease (4%), coronary artery disease (3%), and peripheral vascular disease (15%). More efforts focused on education programmes, and early diagnosis through mass population screening, as well as the improvement of case management may help to reduce the burden of complications.