Type 2 diabetes mellitus is a health problem in low and middle-income countries like Peru. There are few published reports on trends and surveillance of this disease in the young Peruvian population. To describe the prevalence of type 2 diabetes mellitus in the population under 30 registered between 2005 and 2018 by the Ministry of Health of Peru. A descriptive study was conducted from a secondary analysis of the national registries of type 2 diabetes (ICD 10: E11) in the population under 30 treated in the health facilities of the Ministry of Health of Peru between 2015 and 2018. Described by department and geographic region, the prevalence of diabetes was adjusted for age and sex. In the period between 2005 and 2018, the national prevalence of type 2 diabetes mellitus increased from 2.1 to 22.1 cases/100 000 population. Women had a higher prevalence. Geographic regions with the highest prevalence increase were the Coast from 3.8 to 35.3/100 000 population and the Rainforest from 1.1 to 22.1/100 000 population. In the same period, the departments with the highest prevalence increase were Cajamarca (1733.3%) and Puno (1704.2%). Furthermore, Tumbes, Ica, Lambayeque, Callao, Lima, Loreto, and Madre de Dios reported prevalence rates over the national average. The prevalence of type 2 diabetes mellitus in the population under 30 and covered by the Peruvian Ministry of Health has increased more than ten times in the period between 2005 and 2018. The Coast and the cities with the highest population density had the highest prevalence. A greater focus to improve the strategies of risk factor control in the population under 30 is needed, including preventive actions on obesity and inadequate lifestyles, as well as a screening at a younger age for diabetes in the population at risk.