Health literacy (HL) is an essential health determinant that could encourage the adoption of individual and community protective behaviours that contribute to public health. This study aims to analyse the associations between HL and medication HL (MHL) in 4015 adolescents from the Health Behaviour in School-aged Children (HBSC/WHO). Data were collected from the HBSC/WHO questionnaire. Descriptive statistics, bivariate analysis, and multinomial logistic regression were performed. 62.4% of participants have a moderate level of HL and 29.1% have a high level of HL. The youngest boys, and those who have a low level of MHL in the different dimensions presented (expiration date, recycling, side effects, illegal sale and safety), have a low level of HL. The oldest girls have a moderate level of HL. Also, girls with a high level of MHL, reported a high level of HL. MHL, namely, the expiration date, recycling, side effects and safety dimensions in adolescents is significantly related to and positively associated with HL. The results will enable us to highlight to family professionals and public policies the importance of HL and MHL promotion in adolescents.