Objective: The purpose of this study is to examine the impact of parental career support as perceived by adolescents from multicultural families on their career prearation and to investigate the mediating role of self-esteem in this relationship. Methods: For this study, 1,197 high school sophomores were selected from the 8th year of the Multicultural Youth Panel for analysis. Descriptive statistics, correlation analysis, regression analysis, and SPSS PROCESS macro v4.3 were employed to verify the mediation effect focusing on key variables. Results: First, it was found that parental career support positively affects career preparation. Second, parental career support was shown to have a positive impact on self-esteem. Third, self-esteem was found to mediate the relationship between parental career support and career preparation. Conclusions: The study presents practical implications for supporting effective career exploration and planning through parental career support, enhancing career preparation, and bolstering self-esteem among adolescents from multicultural families.