This study explored whether career maturity has a mediating effect in the relationship between high school students' parenting attitude type and school life adaptation. To this end, data from 244 high school students located in N City were collected. Descriptive statistics, correlations, and mediating effects were analyzed using SPSS 25.0 and PROCESS Macro 3.5. The results of the study are as follows. First, positive parenting attitudes were positively correlated with school life adaptation and career maturity, and negative parenting attitudes were negatively correlated with school life adaptation and career maturity. Second, career maturity was found to have a partial mediating effect in the relationship between positive/negative parenting attitudes and adaptation to school life. Through this study, the necessity of intervention in variables related to career maturity was suggested for the intervention of high school students' adaptation to school life.