This study applied the Actor–Partner Interdependence Mediation Model (APIMeM) to examine the mediating effect of co-parenting in the relationship between parents’child values and marital satisfaction, considering both actor and partner effects. Participants were parents residing in Seoul, Gyeonggi, and Incheon, whose children attended kindergartens or daycare centers. Data were collected via an online survey, and responses from 220 dyads were analyzed. The analysis of direct effects revealed that fathers’child values did not significantly predict either their own or their partners’co-parenting perceptions. In contrast, mothers’ child values demonstrated significant actor and partner effects on co-parenting. Regarding the relationship between child-rearing values and marital satisfaction, fathers’values positively influenced their own marital satisfaction(actor effect) but negatively influenced their partners’ satisfaction(partner effect). Mothers’ values showed no significant effects in this relationship. In the relationship between co-parenting and marital satisfaction, both parents exhibited significant actor and partner effects. The mediation analysis indicated that co-parenting did not mediate the relationship between fathers’child values and marital satisfaction. However, for mothers, co-parenting fully mediated both the actor and partner effects in this relationship. Based on these findings, the theoretical and practical implications of this study are discussed, along with its limitations and suggestions for future research.