<![CDATA[Individuals want to find their identities in adolescence, and peers easily influence adolescents. Teenagers will be positive when the individual is in a positive environment, and vice versa will be negative when in a hostile environment. The family becomes the first social environment known to an individual before plunging into other larger social environments. In its development, adolescents become vulnerable to negative influences, including smoking. This study is a quantitative descriptive study with an analytical survey method using a cross-sectional design, which aims to determine the relationship of conformity, parenting and social environment with smoking behaviour in adolescent boys at SMA X in Medan in 2023; it was conducted on 94 high school X students who were carried out by total sampling. Data were collected using questionnaires and analyzed by Chi-Square. Adolescents are affected by conformity to smoking behaviour by as many as 27 respondents (28.7%). Non- democratic parenting (authoritarian and permissive) as many as 62 respondents (66.0%). Poor social environment: as many as 41 respondents (43.6%) There is a relationship between conformity, parenting, and social environment with smoking behaviour Of adolescent boys. Recommendations from this study can be the basis or input for the development and application of counselling guidance services to discuss smoking behaviour that is prone to occur in adolescents and become input for parents to pay more attention to their children's association so as not to be influenced by things and environments that are not good, and always provide examples of good attitudes and behaviour to their children.Keywords: Adolescent Boys, Smoking Behavior, Conformity, Parenting, Social Environment]]>
