Introduction: The increasing incidence of diabetes mellitus and obesity in children is a cause for global concern. These health conditions are interconnected and have serious implications for children's physical and emotional well-being. Additionally, obesity can contribute to other risk factors associated with diabetes, such as high blood pressure and high cholesterol levels. Objective: Discuss childhood obesity, its impacts and its correlation with diabetes mellitus, mainly type 1. Methodology: The integrative review is based on the guiding question ´´ What are the impacts of childhood obesity and its correlation with type 1 diabetes mellitus? 1´´. The research was carried out during the months of January to February 2024, in the LILACS, IBECS and MEDLINE databases with the help of the Boolean AND. After applying the inclusion and exclusion criteria, 06 articles remained used to construct the present study. Results and discussion: It was observed that among the articles selected for the construction of the research, around 66% (04) were published in 2023. While in the years 2022 and 2024, 17% (01) of the selected studies were published in each respective year. Obese children with type 1 diabetes may face additional difficulties adopting a healthy lifestyle. Final considerations: Importance of health education and promotion, as well as changing lifestyle habits.