Prevalence of Diabetes Mellitus among patients attendingTabaka Mission Hospital, Kisii County . ABSTRACT In today’s world, 180 million people are suffering from diabetes. Out of these, 162 million have type 2 diabetes. Type 2 diabetes, a state of diminished systemic sensitivity to insulin, has its root in the lifestyle of the subjects. The prevalence of diabetes in the WHO African Region was estimated at 1.02 million (10%) had type 1 diabetes and 6.3 million (90%) had type 2 diabetes. The main objective of the study will be to determine the prevalence of Diabetes mellitus among patients above 18 years attending Tabakamissin hospital, kisii County. The study will adopt quantitive descriptive cross sectional as it will be hospital based. The study shall employ only 100 patients selected systematically out of total patients tested will represent all patients who will be tested. blood specimen will be used in analyzation of Diabetes mellitus. The method can be used on cases of emergency, it is reliable and easy to use. The study data shall be presented by use of bar graphs and pie charts. Ethical issues shall be adhered where research shall be carried upon grant of permission from relevant authorities.