The purpose of this study was to understand the forming and activities of the elementary school teachers-initiated research organization. For this purpose, a qualitative case study was conducted on Hansung Teachers\' Research Organization for Physical Education(H-TROPE) and four members who participated in that research organization. Data were collected through participant observation, in-depth interview, and documentation, then were analyzed by inductive categorized analysis. We found that according to the major affairs happened, forming process of H-TROPE was devided into three periods: the quickening period, growing period, and transition period. And the aims members participate in H-TROPE were revealed as developing own profession, activating physical education, and making personal network. The major activities of H-TROPE included training program and workshop for teachers, consulting, publication of bulletin, managing homepage, and so on. The cultural characteristics of H-TROPE are discussed in terms of apprenticeship and purposeful collaborative group. ※ Key words : research organization, subject-matter collaborative, teacher professional development.