Objective: This study aimed to describe the periodontal condition of adolescents and identify its potential determinants. Methods: This is a cross-sectional population-based study (n=763) conducted in a city in Northern Minas Gerais. Multistage probability cluster sampling method was used. Trained and calibrated professionals carried out the intraoral examinations and the interviews at the participants’ homes. Logistic regression model was used to identify the factors associated with the periodontal condition. Results: It was found that around 30% of the adolescents presented periodontal changes, being gingival bleeding (14.1%) and dental calculus (14.0%) the most prevalent impairments. Periodontal changes were associated in adolescents who did not attend school (OR=1,9; p=0.031), attended public schools (OR=2,0; p=0.005), never went to the dentist (OR=1,7; p=0,047), used public/philanthropic services (OR=1,7; p=0,002), smoked (OR=1,6; p=0,003), consumed alcohol (OR=1,6; p=0,016) and self-perceived their oral health as too bad/bad (OR=2,4; p=0,032) and regular (OR=1,5; p=0,023). Conclusion: About one-third of adolescents have periodontal changes, which were associated with the type of school and type of dental service they attend, smoking, alcohol consumption and self-perception of oral health.