The objectives of this research are: (1) To study the current situation and need for developing professional learning community in primary schools; (2) To develop the model for developing professional learning community, and (3) To study the findings of development for professional learning community based on developed model related to knowledge, comprehension, and competency in developing professional learning community, teaching behavior and students' quality. The research area was purposively selected three primary schools. Participatory Action Research was administered in 6 phases; there were 7458 participants. The instrument used for data collection in this study was questionnaire. The statistics used were frequency, percentage, mean, and standard deviation. The findings are as follows: (1) The current situation in developing professional learning community showed that the administrators' overall opinion in all 5 aspects is in "High" level; (2) The model for developing professional learning community consisted of 4 major factors: (a) Preparation for learning organization; (b) Development of shared norm and value; (c) Learning from common work practice, and (d) the expected outcome. (3) The evaluative finding of teachers' knowledge, comprehension, and competency in developing professional learning community was in "high" level.