Until now, intercultural communication researches have been focused on motivation, behavior, and skills involved in the intercultural relation as well as on the efforts of mediating intercultural and inter-religion conflicts. Few researches have been done in the matters of how social harmonization in diverse religious society is formed. This paper offers a new theoretical model to study social harmonization processes in diverse religious society by incorporating Relational Dialectics Theory (Baxter, 2004) and Structural Functionalism Theory (Parsons, 2005), especially the AGIL scheme which-according to Parsons-are conditions need to be meet for society to maintain stable social life. The theoretical approach proposed in this paper is considered new in the field of intercultural communication, especially in the context of diverse religious society. This paper also proposes the communication ethnography as the research method that is suitable to the theoretical approach to be use in studying harmonization processes in a diverse religious society.