Using data from the second wave of Busan Education Longitudinal Survey(BELS), the study analyzed the influence of parent s school activity participation on elementary school student s academic achievement and provided the implications of policy for activating parent s school activity participation. The school activity participation of parents of elementary school students consists of school activity participation in parent level and school activity participation in school level. The variables of the parent level include parent s socioeconomic status, parent s educational support, parent-child relationship, number of the parent s school activity participation, and parent s school satisfaction, and the variables of the school level include number of person of parent s monitoring, number of parent s monitoring, perception of principal s parent or community, and perception of teacher s parent or community. The main results are as follows: First, the parent s socioeconomic status, the parent s educational support, parent-child relationship, and the number of the parent s school activity participation influenced elementary school student s academic achievement positively in the parent level. Second, the number of the parent s monitoring influenced elementary school student s academic achievement positively, but the perception of teacher s parent or community relationship influenced elementary school student s academic achievement negatively in school level. Based on the results, the political implications and suggestions were discussed.