Objective: To analyze the trend in hospitalizations for diabetes mellitus in a period of 15 years, according to gender and age group. Methods: Descriptive study, with time series data from hospitalization for diabetes mellitus in individuals of both genders, aged 20 or more, data obtained in the information system of the unified health system and analyzed according to descriptive statistics and polynomial regression. Results: A total of 117,717 hospitalizations were registered, 61.6% were women. The general trend was stable, although it has been increasing for men (r(2) = 0.83; p<0.001) and stable for women. Age group 50-59 and older than 80 years (r(2) = 0.78; p<0.001 for both) showed increasing trend for men, while for all ages it was stable or it was declining for women. Conclusion: The trend in hospitalization for diabetes mellitus stratified by gender and age was increasing just for men in the age group of 50-59 years and older than 80 years.