Objective: The purpose of this study was to examine the mediating role of the father s play participation in the relationship between father playfulness and father-child intimacy. Methods: We conducted a survey of 500 fathers with 3~5 years olds attending kindergartens and located in Seoul and Gyeonggi province. Father s Playfulness Scale, Father s Play Participation Scale, and Father-Child Intimacy Scale were used as data measuring tools. The data collected in this study were analyzed using SPSS 22.0 Program. Results: As a result of examining sub-variables of play participation among fathers, it turned out that mediating effects occurred in physical play, role play, and function play. Conclusion/Implications: The results of this study suggest the necessity of developing a father education program to increase the intimacy between father and child as the role of father becomes increasingly important in the age of co-parenting.