This study examined the relationship between parental financial communication and experiential learning during the growth period, and retirement account management practice in adulthood. We focused on the mediation effects of objective and subjective financial knowledge between family financial socialization and retirement account management practice. Utilizing data from the 2022 Financial Well-being Survey, we applied multiple linear regression, multinomial logistic analysis, and the Karlson-Holm-Breen (KHB) method to analyze mediation effects. The major results were as follows: First, the correlation coefficient between objective and subjective financial knowledge was very low, suggesting that these two concepts are distinct. Second, parental financial communication was significantly associated with subjective financial knowledge, while financial experience was significantly associated with objective financial knowledge. Third, subjective financial knowledge had a significant effect on retirement account management practice, unlike objective financial knowledge. Fourth, the influence of parental financial communication on retirement account management practice was significantly mediated by subjective financial knowledge, with the direct effect being more pronounced than the indirect effect. Our results suggest that financial education programs should focus on enhancing both types of financial knowledge, with an emphasis on the subjective aspect to more effectively influence retirement account management behaviors.