BackgroundThe COVID-19 pandemic has underscored the impact of Social Determinants of Health (SDH) on adolescents' Quality of Life (QoL), especially in vulnerable communities. While most research has focused on adults or general clinical conditions, this study addresses the gap in adolescent-specific COVID-19 impacts, emphasizing SDH's role in Brazilian youth's health outcomes. MethodologyThis cross-sectional study analyzed 235 adolescents from 89 cities in a northeastern state of Brazil, registered in the Unified Health System's notification system, with data collected nationally in 2022 and referring to the years 2020, 2021 and 2022. Statistical tests, including the Levene test for variance equality, Student's t-test, and ANOVA with a 95% confidence interval, were used, supplemented by the Games-Howell multiple comparison test. The study found lower scores in vitality and mental health domains. Males showed higher scores across all domains (p < 0.001). ResultsAdolescents aged 10 to 14 scored higher in the vitality domain. Those who engaged in physical activity had better scores in general health, vitality, and mental health domains. Adolescents with sleep difficulties had lower scores in pain, general health, vitality, and mental health domains. Additionally, those living with high-risk individuals had lower scores in vitality and mental health domains. ConclusionSDH related to demographic factors, physical activity, and sleep quality significantly impacted adolescents' QoL, particularly affecting vitality and mental health.