IntroductionMonitoring type 1 diabetes (T1D) trends across most European countries using objectively measured data and how this incidence has evolved over the past three decades should be considered a public health priority. This study protocol provides a standardised and transparent methodology to assess TD1 trends among 0–14-year-old children and adolescents across Europe from 1994 to 2021.Methods and analysisThis protocol is guided by the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols and the Cochrane Collaboration Handbook. The literature search will be conducted using MEDLINE, Embase, CINAHL and Web of Science databases from 1994 to 2021. Observational cohort studies providing incidence rates for European children and adolescents diagnosed with T1D aged ≤14.9 years and studies written in English, Spanish or Portuguese will be included. The risk of bias of the included studies will be assessed using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies from the National Heart, Lung, and Blood Institute. Subgroup analyses will be performed based on gender, age, study year, country or European region. Metaregression analysis will be conducted using economic and geographic variables, such as gross national income of the country or geographic latitude.Ethics and disseminationThe systematic review based on this protocol will provide a comprehensive description of T1D incidence trends in children and adolescents across Europe from 1994 to 2021. The results will be disseminated in a peer-reviewed journal and in mass media. This study will exclusively use data from published research, so institutional ethical approval is not required.PROSPERO registration numberCRD42021239480.