Diabetes mellitus is a chronic metabolic disease characterized by disorders in the metabolism of carbohydrates, fats and proteins that result in relative or absolute lack of insulin. The purpose of this study was to evaluate the oral health of patients with diabetes mellitus type 2. Twenty-four patients with diabetes and twenty-eight control subjects participated in the study. Processing of subjects consisted of history questionnaire, clinical examination of oral cavity and diagnostic procudures. Patients with diabetes had a higher prevalence of dry mouth, burning mouth syndrome and changes in sense of taste of food and beverages. Most frequent changes on the oral mucosa were inflammation, prosthetic stomatitis and tounge atrophy. Prevalence of oral candidiasis in patients with diabetes is significantly higher than that in the control group. Patients with diabetes had significantly less saliva then control subjects. From the results we can conclude that type 2 diabetes affects oral health and impairs it, and therefore should pay particular attention to maintaine oral health of patients with diabetes in order to prevent the development of oral complications and promptly treat already existing complications.