Objective: Variability in the incidence of type 1 diabetes mellitus (T1DM) related to geographical region, ethnic background, gender, and age indicates a need for further epidemiological studies. To date, there are no reported studies on the incidence of T1DM in the pediatric age group from the Southeastern region of Turkey. To define the incidence, demographic and clinical characteristics of T1DM in children 0-14 years of age in Diyarbakir, one of the largest cities in the Southeast region of Turkey.Methods: Hospital files of patients with the diagnosis of T1DM were reviewed. Data of all patients diagnosed between 1 June 2010 and 31 May 2011 were evaluated. Population data on the 0-14 age group were obtained from the Turkish Statistical Institute (TSI) reports.Results: From a total of 41 T1DM patients, 24 (58.5%) were female (male: 41.5%) with a male/female ratio of 1.4. The overall annual incidence of T1DM was 7.2/105, being 8.7/105 in females and 5.7/105 in males. The peak incidence was found to occur at age 5-9 years in the girls and 10-14 years in the boys. Mean age at diagnosis was 8.1±3.8 years. Rate of presentation with diabetic ketoacidosis was 65.9%. Patients applied most frequently in spring and winter months.Conclusions: In this first T1DM incidence study on the pediatric age group in Diyarbakir, Turkey, T1DM incidence was found to be similar to that in countries with low-middle incidence. Conflict of interest:None declared.