Food insecurity in recent years has increased worldwide due to many planetary events such as the COVID-19 pandemic, geopolitical conflicts, the climate crisis, and globalization of markets. Adolescents are a particularly vulnerable group to food insecurity, as they enter adulthood with less parental supervision and greater personal autonomy, but less legislative or institutional protection. The experience of food insecurity in adolescents is influenced by several environmental factors at different levels (interpersonal, organizational, community, and societal), although they are not usually addressed in the design of interventions, prioritizing the individual behavioural factors. We present a scoping review protocol for assessing and identifying the environmental factors that could influence adolescents' food insecurity. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P) and the PRISMA guidelines for Scoping Reviews (PRISMA-ScR) to prepare the protocol. The search strategy will be performed in the following databases: Pubmed/Medline, EMBASE, Biblioteca Virtual de Salud, EBSCOHost, Scopus, Web of Science, and Cochrane Library Plus. The reference list of the included studies will also be hand-searched. Grey literature will be search through the electronic database Grey Literature Report, and local, provincial, national, and international organisations' websites. Assessment of eligibility after screening of titles, abstract and full text, and the resolution of discrepancies will be performed by three independent reviewers. This scoping review will contribute to refine the "logic model of the problem" which constitutes the first step in the intervention mapping protocol. The "logic model of the problem" from the intervention mapping protocol will serve to classify and analyse the environmental factors. The findings from this review will be presented to relevant stakeholders that have a role in shaping the environmental factors.