The purpose of this study is to identify the effect of self-efficacy and motivation related with extra-curriculum music activity for elementary school students. Utilizing a questionnaire method, it targeted 341 students in third, fourth, fifth and sixth grades(163 participants, 178 non-participants) except for materials responded frivolously among 390 girls in Seoul. Self-efficacy breaks down into three subordinate domains (cognitive, social-emotional and psycho-motor aspects) and learning motivation does four subordinate domains (positive internal motive, negative internal motive, positive external motive and negative external motive), so the following can be concluded through the data analysis. First, it was demonstrated that the children who participated in extra-curriculum music activity were higher in self efficacy and motivation than other children who didn`t. Second, girls were higher in self efficacy and motivation than boys. Third, third and fourth graders were higher in self efficacy and motivation than fifth and sixth graders. The lower a grade was, the higher self efficacy and motivation were. Fourth, the children who participated for more than 1 year were higher in self efficacy and motivation than other children who didn`t. Fifth, self efficacy and motivation, especially, had a strong positive correlation toward student`s cognitive, social-emotional, and psychomotor aspects. Therefore, this study shows that extra-curriculum music activity can positively affect elementary school students` self efficacy and motivation.