This study explores the effects on development of poor children by community-based orchestra educational activities and the orchestra educational activities factors for promoting the effects using longitudinal data are those collected for "The Evaluation of the Impact of Our Neighborhood Orchestra on Children's Learning" made by the Seoul Philharmonic Orchestra. For these purposes, this study employed a latent growth model analysis of the factors such as depression, aggressive behavior, communality and interpersonal relationship of development of poor children and evaluation, satisfaction, outsiders'attention and participation of facilitative factors. The result shows that they displayed significantly positive development in depression, aggressive behavior, and interpersonal relationship. It appears that the evaluation on music achievement had a positive impact on the rate of change in communality, while the evaluation on attitude had an impact in the initial value of depression, aggressive behavior, and communality, also the sense of satisfaction had a positive impact on the initial value of communality and interpersonal relationship in conditional models. And parents' attention and participation had a negative impact on the initial value of aggressive behavior, while the attention and participation of the community showed a positive impact on the initial value of depression and aggressive behavior. Based on these results, this study attempted to broaden the understanding of the development of poor children taking part in orchestra-based educational activities and provide a practical basis for social workers' direct invention, and look for new ways by shedding light on the merits of the cultural/art education of poor children that engage in the community-based orchestra educational activities.