OBJECTIVE To study the prevalence of glucose intolerance in adult urban and rural populations in the northern parts of Sudan. RESEARCH DESIGN AND METHODS A sample of 1,284 subjects aged ≥25 years was selected using a multistage cluster method and underwent a 75-g oral glucose tolerance test. RESULTS The crude prevalence was 3.4% (men, 3.5%; women, 3.4%) for diabetes and 2.9% (men, 2.2%; women, 3.3%) for impaired glucose tolerance (IGT). The highest crude prevalence was in the northern parts of Sudan (5.5%) and the lowest in the western desert-like parts (0.9%). Diabetes and IGT rates were not different between the urban and rural populations. New cases (2.2%) were almost twice as prevalent as previously known cases (1.3%). Family history of diabetes, obesity, and advanced age were associated with higher rates of diabetes. CONCLUSION The results showed a high prevalence of diabetes in the adult population of Sudan, with a wide difference among the different areas. The high ratio of newly discovered to previously known diabetic cases may reflect poor public awareness and medical services. These findings will certainly have far-reaching implications for diabetes care delivery in this country.