Background. Insulin pump therapy in increasingly frequently used in the Russian Federation in recent years, which requires an evaluation of the treatment in order to improve its efficacy and safety. Objective — the study was aimed at complex monitoring (long-term efficacy and safety, state of medical care, factors associated with metabolic control, and factors hindering its use) of the continuous subcutaneous insulin infusion (CSII) in children, adolescents, and young adults with type 1 diabetes mellitus (DM1) from various regions of the Russian Federation. Material and methods. Data of 395 DM1 children and adolescents from 60 regions of the Russian Federation were collected from the pediatric CSII register of the Endocrinology Research Center. The following data were analyzed in different age groups (0 to 7 years, 8 to 11 years, 12 to 17 years, and 18 to 25 years): glycemic control, the incidence of acute complications, discontinuation of CSII, characteristic features of blood glucose monitoring, and supplies coverage. Results. Initiation of CSII is accompanied by decrease in HbA1c level with the lowest values within the period from 6 to 24 months (–0.7±1.5% compared to the baseline level). However, 6 years after CSII initiation, HbA1c values do not differ significantly from the baseline values. The target HbA1c level (less than 7.5%) is observed in 43.6% of children aged 0 to 7 years, 32.7% of children aged 8 to 11 years, 24.2% of adolescents aged 12 to 17 years, and 28% of young adults aged 18 to 25 years. Regular self-monitoring of glycemia, 4 and more times per day, was performed by 83% of patients, while the frequency of continuous glucose monitoring (CGM) was low, 12.7% in the whole population. The incidence of acute complications in children and adolescents under 18 years did not differ significantly and the lowest incidence was observed in the age group 18 to 25 years. The effectiveness of CSII depended on the frequency of self-monitoring, CGM use, and supplies coverage. CSII discontinuation rate was 4.6 cases per 100 patient-years. The main reasons for discontinuation of CSII included the inconvenience of its use and the cost of supplies. Conclusions. Many children and the majority of adolescents with DM1, who use CSII, did not reach target HbA1c level despite the adequate self-monitoring. Many patients do not use CGM and refuse CSII. This necessitates the efforts to improve the efficacy and overcome barriers to the use of CGM and CSII.