In research studies performed to enlighten the diagnosis and pathogenesis of various diseases and to investigate possible treatment strategies, experimental animal models provide many advantages to the investigators. Diabetes Mellitus is a chronic metabolic disease which lasts for whole life, requiring continuous follow-up and therapy. With its acute and chronic complications, it decreases patient's lifespan and quality, causes a high morbidity and mortality rate and is a huge economic burden. Therefore clarifying its pathogenesis has a great value. In this review, experimental models and their application procedures used in research studies examining pathogenesis of diabetes and its therapoetic approaches are discussed.