Parents play a key role in young athletes’ sport experience. In particular, parents’ sport goals for children may influence young athletes’ morally relevant sport behaviors. The present study involves 172 Italian adolescents (female = 51.7%; age M = 15.41, SD = 1.73) practicing team sports and analyzed whether and the extent to which parents’ sport socialization values, those values adolescents perceived their parents wanted them to endorse (i.e., moral, competence, status values), were associated with young athletes’ antisocial behaviors towards teammates and opponents. Adolescents’ perceptions of the prominent motivational climate (i.e., mastery and performance) within their team were also considered. Participants were asked to fill out questionnaires, including the Youth Sport Values Questionnaire-2, adapted to measure adolescents’ perceptions of parental socialization values, the Perceived Motivational Climate in Sport Questionnaire and the Prosocial and Antisocial Behavior in Sport Scale. The results of multiple linear regression analysis and relative weight analysis showed that mastery motivational climate, as protective factor, and mothers’ status values, as risk factor, were the most important variables in predicting adolescents’ antisocial behavior towards teammates. As far as adolescents’ antisocial behavior towards opponents was concerned, performance motivational climate and mothers’ status values were the most relevant predictors: the more adolescents perceived their coaches and mothers as giving importance to performance and status, the higher was the frequency of their antisocial behavior in sport. Implications and further developments of the study are discussed.