Problem Statement: Currently, primary schools in Thailand had been assessed for quality education by external personnel. The results of such assessments were that many schools failed to pass the approval standards. Bringing some disappointment to the people who involved in school running and those who sought educational services. Many lost their confidence in schools; many were not satisfied with schools. The whole problems were believed to come from or caused partially by organizational culture. Organizational culture consisted of many elements, such as, belief, behavior, recognition, traditions, and rituals. Such were known as identity and were passed down from previous generations. Some elements were tangible, such as, school buildings and school environment. The objectives of the study was there fold. 1) to study the historical background of the Sub-Districts' good schools in Isan, Thailand, 2) to investigate the current situations of school organizational culture of the Sub-Districts' good schools in Isan, Thailand, and 3) to study development model of organizational culture for quality enhancement of educational administration of the Sub-Districts' good schools in Isan, Thailand. The study was carried out in 3 Provinces in Isan: Nakhon Ratchasima, Buri Ram, and Chaiyaphum. Six schools were selected as sample. Materials and Method: The research method used was qualitative. The data were collected using a basic survey, observations, interviews, focused group discussions, and workshops. The 144 informants were divided into 3 groups: 18 key informants, 102 casual informants, and 24 general informants. The fieldwork was carried out between May- August, 2011. Result: 1) Historically, each village was built by village families that moved from elsewhere. Most of them were farmers. The government then had a school built for each village. Since most village schools were located in the Buddhist temple ground, teaching was done using temple buildings. Later, village schools were built independently using the government support. When schools had enough teachers and buildings, teaching had continually been improved. Many schools participated the 2010 Sub-Districts' good schools project. 2) Currently, the organizational culture of Sub-Districts' good schools specifically the school administration had mission frame worked structure using educational development plans, internal quality assurance, and students' accentuate learning. There was a variety of learning activities, class-rooms arrangements, and student support. The schools emphasized students' rights, respect of team work members, working happily together, making school clean, pleasant, and safe like home. For school participation, the schools reinforced as well as supported all concerned partners to participate in school educational development. 3) A development model of organizational culture for quality enhancement of Sub-Districts' good school administration in Isan, Thailand was done by an operation plan specified for creative change and school advancement in areas of administration, personnel, students' learning, school environment, school atmosphere, school participation, students' support, innovation and technology, learning centers, and community services. Conclusion and recommendation: The study explained the historical background of school organizational culture, current situations, and development model of organizational culture for quality enhancement of Sub-Districts' good schools in Isan, Thailand. The results could be applied for school organizational culture in other parts of Thailand.