Background: Vitamin D plays an important role in the immune system and consequently in the inflammatory process of asthma. It acts directly on the regulation of Th1 and Th2 cells and regulatory T lymphocytes. Evidence shows that vitamin D can act on dendritic cells, raising inflammatory mediators and increasing the imbalance between Th1, Th2, and Th17. Understanding the link between vitamin D and inflammatory processes in the control and severity of asthma is important for the existence of specific therapies. Objective: We aim to synthesize the scientific evidence about the role of Vitamin D in the control and severity of asthma in pediatric patients by a systematic review. Methods: A systematic and comprehensive search will be performed using MEDLINE PubMed, BIREME, EBSCOhost, Scopus, Web of Science, EMBASE, Cochrane Library, and ProQuest. From the data obtained, all the articles found will be transferred to the Rayyan platform. Study selection will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist (PRISMA-2020). Additionally, if sufficient data are available, a meta-analysis will be conducted.Discussion: The ability of vitamin D to act in the immune system with a direct action on the inflammatory asthma cascade, allows for a better understanding of the disease. This will lead to better asthma management, and, consequently, to help in controlling the disease. The conduction of a systematic review will bring better knowledge about vitamin D and its role in the pathophysiology of asthma Systematic review registration:This protocol has been registered in the PROSPERO and the registration number is CRD42021221638.