Nowadays, problematic internet use (PIU) in adolescence is serious. Understanding the antecedents of problematic internet use in adolescence is the precursor of effective prevention and intervention. A large body of literature shows that temperament (sensation seeking and effortful control) and parenting styles (authoritativeness, authoritarianism, and permissiveness) are closely related to PIU in adolescence. Nonetheless, our understanding of the association among these variables is limited in several ways. First, there is a paucity of research that examines the unique effects of temperament and parenting styles on PIU in adolescence. Second, few study examined the interaction effects among temperamental factors on PIU in adolescence. Third, the existing research is not clear whether there are interaction effects between temperamental factors and parenting styles. The purpose of the present study is to investigate: (1) the unique associations of temperament and parenting styles with PIU in adolescence; (2) the interaction effect among temperamental factors on PIU in adolescence; (3) the interaction effects between temperamental factors and parenting styles on PIU in adolescence. A sample of 1312 participants of 6 schools (659 boys and 653 girls, the average of age 13.43) was recruited in the study to complete self-report questionnaires. The self-report questionnaires used in this study included Early Adolescent Temperament Questionnaire (Revised Version, Short Form), Parenting Styles and Dimensions Questionnaire, and Problematic Internet Use Questionnaire. The results indicated that: (1) sensation seeking, effortful control and authoritarianism parenting were significantly associated with PIU in adolescence, while authoritative parenting and permissive parenting were not significantly associated with PIU in adolescence. (2) the risk effect of sensation seeking on PIU in adolescence was buffered by effortful control. (3) the risk effect of sensation seeking on PIU in adolescence was buffered by authoritative parenting, but enhanced by permissiveness parenting. No other interaction effects were found. These findings underscore the importance of unique effects and interaction effects in understanding the etiology of PIU in adolescence. The theoretical and practical implications of the results were further discussed. First, we should attach importance to the effect of temperament (sensation seeking and effortful control) on PIU in adolescence, and enhance the prevention of temperament. Second, parents should adopt authoritativeness parenting, and avoid adopting permissiveness parenting in order to reduce the effect of sensation seeking on PIU in adolescence. Third, adolescence with low effortful control and high sensation seeking characteristics, low authoritativeness parenting and high sensation seeking characteristics, or high permissiveness parenting and high sensation seeking characteristics are high risk crowd of PIU.