Resumen: Objective. Shed light on the experiences and determinants of young people’s and adolescents’ participation in formal participation mechanisms during the SARS-CoV-2 pandemic in Chile. Methods. Cross-sectional, descriptive study with a qualitative approach, within the constructivist research paradigm. Three focus groups were conducted with key informants: young people and adolescents who regularly participate in advisory councils of Chile’s Ministry of Health (MINSAL). Content analysis was applied for theoretical and emerging categories in the study. The reports were transcribed and studied with data analysis and hermeneutics. This study was conducted during the COVID-19 pandemic, between the months of March and November 2021. Results. During the pandemic, adolescents’ and young people’s experiences of health participation were affected; however, formal participation mechanisms such as advisory councils allowed for continuity. In this context and based on their experiences, young people and adolescents highlighted some factors that facilitated or limited their participation at three levels: individual, relational, and structural. They highlighted virtual communication, use of social networks, and digital health as excellent tools for the participation of young people and adolescents during the pandemic in Chile. Conclusion. The pandemic affected the participation mechanisms used by young people and adolescents in Chile; however, among the experiences highlighted by young people, aspects that facilitated participation emerged, such as virtual communication, digital health, and other strategies. At the same time, some gaps in health participation widened during this global health crisis, such as access mainly in rural populations.