Adolescence is a critical period for the development of affectivity and sexuality. Adolescents begin to explore their sexual identities, form intimate relationships, and learn to manage their emotions in new and complex contexts. This study aims to analyze the prevalence of habits and behaviors related to the affective-sexual health of adolescents in the fourth year of ESO, identifying risk factors, comparing their behaviors and risks, monitoring these behaviors, analyzing their pornography consumption, and evaluating the use of the internet as a source of sexual information. Descriptive cross-sectional study using questionnaires. Participants are fourth-year ESO students from a school in the Baix Llobregat province (Catalonia), aged between 14 and 18 years. Descriptive and bivariate statistical analyses are conducted using the chi-square test and p-value calculations with the R Project software. Frequency and percentage analyses are also used to describe the health behaviors of the participants. The study reveals that girls have better knowledge of the contraceptive pill and male condom than boys. Sexual initiation and condom use management vary between the genders, with girls being more capable of persuading their partners to use them. Pornography consumption also shows significant differences in terms of the age of initiation and frequency between boys and girls. This study on adolescent affectivity and sexuality reveals knowledge about contraceptives, early sexual initiation, and high pornography consumption, highlighting the need for early and diverse affective-sexual education, youth empowerment, and media misinformation management to promote safer and healthier behaviors within municipal public health.