Background: Social, emotional, and behavioral problems in childhood are key predictors of persistent problem behaviors throughout the life courses of individuals. Early parental intervention training, as an important preventive measure, plays a critical role in improving the social, emotional, and behavioral (SEB) development of children.Method: We conducted a systematic review and meta-analysis to analyze the intervention effects of the latest literature on Triple P (Positive Parenting Program), which is a multilevel system that provides treatment and prevention for children at risk of social, emotional, and behavioral problems via parenting approaches to enhance the parenting knowledge, skills, and confidence of parents. Since the literature on Triple P from 1970 to 2012 has already been systematically reviewed, this study searched the literature from 2013 to 2020 from the Web of Science, EBSCO, ERIC, MEDLINE, CNKI, and Triple P Evidence-Base website using multiple search strategies. This study differs from the existing research by its inclusion criteria of studies that use experimental designs or quasi-experimental designs. A total of 37 studies were included in the final analysis, and STATA 16.0 was used for evaluation while RevMan 5.3 for risk of bias assessment.Results: The results show that Triple P can promote the social competence of children (SMD = 0.274) and prevent their emotional (SMD = −0.254) and behavioral problems (SMD = −1.38) to a certain extent. Simultaneously, the proximal effects on parents mainly included changing negative parenting styles (SMD = −0.46), reducing parenting conflicts (SMD = −0.311), and improving parenting efficacy and self-confidence (SMD = 0.419). The distal effects on parents included reducing the psychological adjustment problems of parents (SMD = −0.265), improving parent–child relationships, and reducing parent–child conflict (SMD = −0.714). However, the meta-analysis results did not show a significant effect of Triple P on improving the marital relationship quality and satisfaction of parents (SMD = 0.063). Components of the program intervention, including intervention level, service delivery format, service method, and program implementation setting, and the age of the children were crucial moderating factors on the outcomes of Triple P.Conclusion: This study systematically reviewed the latest Triple P intervention literature and found the significant effectiveness of Triple P on the SEB problems of children and parenting outcomes and the moderators of the effect size.