Abstract
Prior research has separately investigated the associations of autonomy-supportive parenting and narcissism with adolescents’ prosocial behavior, but their joint relationships with prosocial behavior have been rarely examined. The present research aimed to expand the existing literature by scrutinizing the main and interactive associations of autonomy-supportive parenting and narcissism with adolescents’ prosocial behavior. In so doing, a series of four studies (collectively N = 2023), combining cross-sectional, longitudinal, and experimental designs, were conducted. The adolescents’ mean age varied from 12.42 to 15.70 years, with a balanced representation of the sexes in those studies. Converging results across four studies showed that high narcissism magnified the positive association between autonomy-supportive parenting and adolescents’ prosocial behavior. The interaction pattern presented also suggested adolescents with high narcissism scores were more affected than others—both for better and for worse—by autonomy-supportive parenting, although this interaction might be specific to particular facets of prosocial behavior. These results were robust after adjusting for a few key covariates and survived a set of additional analyses. The present findings provide a novel avenue to explain individual differences linking prosocial behavior with those two factors and further advance precise, individualized strategies to promote adolescents’ prosocial behavior.