This study is designed to explore both the direct and indirect effects of adolescents’ personality traits as well as the psychological family environment on their social problem-solving abilities in the path of their effects on self-esteem and peer relationship skills for middle school student. In this study, a survey was conducted of 558 male and female adolescents–1st, 2nd and 3rd graders–in two middle schools in Gyeonggi Province, Korea. We used SPSS 21.0 and Mplus 7.0 to analyze the surveys, and the result is as follows. First, self-esteem served as a partial mediation while there was the effect of self-directedness, with the sub-factor of personality trait, on social problem-solving abilities. the effect of cooperativeness, another sub-factor of personality trait, on social problem-solving abilities, with their peer relationship skills being significant. Meanwhile, the effect of cooperativeness on self-esteem was not significant. Second, the effect of psychological family environment on self-esteem and peer relationship skills showed a positive significance while the effect of self-esteem on social problem-solving abilities showed significance. Meanwhile, the direct effect of psychological family environment on social problem-solving abilities was not significant. Such results demonstrated that only self-esteem was a mediating variable among the impacts of personality trait and psychological family environment on social problem-solving abilities for middle school student.