Objectives: To study the incidence trend of type 1 diabetes mellitus (T1DM) in children in Beijing from 1995 to 2010, to compare it with incidences reported worldwide and to predict the requirement of medical resources in the future. Methods: This study involved newly diagnosed T1DM cases younger than 15 years of age in the Beijing Children's Hospital from January 1995 to December 2010. We calculated the incidence of T1DM children in Beijing according to hospitalization data and Beijing's population. We defined it as the underestimated incidence rate (UE-IR). Results: The UE-IRs of T1DM ranged from around 0.88/100,000 to 2.37/100,000 for children in Beijing younger than 15 years of age from 1995 to 2010. The UE-IR increased faster in boys (1.47 times) and in the age group of 0-4 years (1.89 times) after 2003. The UE-IR was greatest in children aged 5-9 years (1.81/100,000) followed by the age of puberty (10-14 years, 1.76/100,000). The predicted number of new T1DM cases in Beijing will increase 1.97 times over the next 10 years. Conclusions: The incidence trend of T1DM was increasing gradually in those younger than 15 years of age in Beijing. The incidence of younger children and boys grew faster. The 5- to 14-year-old children represented a high-risk population of T1DM. The number of predicted new T1DM cases will grow rapidly. This means that we should train more health care providers for pediatric diabetes patients, in order to achieve high-quality medical care and to be able to prevent or postpone chronic complications. (C) 2013 S. Karger AG, Basel