Objective: The purpose of this study was to investigate the effects of fathers playfulness and play participation on preschoolers peer competence. Methods: The participants in the study were 325 preschoolers and their fathers. The survey method was used to investigate fathers playfulness, fathers average level of play participation as well as playtime with their children and preschoolers peer competence. In order to analyze the data, one-way ANOVA and regression analysis were utilized. Results: The results showed that fathers playfulness and play participation were different according to the fathers weekly working hours. It was found that the higher the cheerfulness of the sub-factors of fathers playfulness was, the higher the sociability of sub-factors of preschoolers peer competence was. The amount of fathers play time with children as well as the average level of play participation, which is the qualitative aspect of fathers play participation, was found to affect preschoolers peer competence and the three sub-factors of competence. Conclusion/Implications: The findings implied that fathers active play participation with children is important and that there is a need to improve working conditions in order for fathers to have time to play with their children.