BACKGROUND: The quality of social relations in adolescence is possibly one of the major determinants of habits that can influence the health of young people, and it may also be one of the mediators of the effect of social position on health. In this paper we propose to test these hypotheses for Italian adolescents, in order to suggest interventions aimed at improving their health. METHODS: The Italian data of the HBSC (Health Behaviour in School-Aged Children) survey 2001-02 have been analysed, and the distribution of the perceived quality of social relations has been described, stratified by age, gender, and economic well-being. Logistic models have been fitted using health behaviours as dependent variables and economic well-being and social relations as determinants. RESULTS: The quality of relations with adults seems to decrease consistently from age 11 through age 15, while the relation with peers improves. The relation with the father seems positively correlated with economic well-being. Difficult relations with adults are associated with higher probability of smoking, drinking alcohol and using cannabis; difficult relations with peers are associated with lower physical activity and lower probability of having used cannabis. CONCLUSIONS: Even if the relations with adults become less important in adolescence, they are still associated with health behaviours. Our results fit the framework of socialization theories and can be used for planning adequate health education interventions.