The main purposes of this thesis were to study a history and development of Sangha, ecclesiastical administration of Sangha in the Nampong district, and an effect of ecclesiastical administration on Buddhists in the Nampong district, Khon Kaen Province. This study was a qualitative research. It was found in the following points.

                   About a history and development of Sangha, it was found that in the Buddha’s time, the Buddha was a leader of ecclesiastical administration. Later, he assigned Sangha to manage all ecclesiastical business such as ordination of a novice, ordination of a monk, and Sangha administration. The Buddha issued discipline as law for all monks. In the present time, the Sangha Supreme Council added some rules that were suitable for the social changes and agreeable to the issued discipline mostly derived from the past time.

                  About ways of ecclesiastical administration in the Nampong district, Khon Kaen province, it was found that it was divided into six aspects. The first was administration actually done under the Buddha’s teachings, discipline, and rules issued by the Sangha Supreme Council in Thailand. The second was the Pali teaching school. The third was educational aids—the Buddhist secondary school and the Buddhist meritorious school. The fourth was the spread of the Buddha’s teachings such as establishment of Sisapawan Insight Meditation Centre, Nampong district, Khonkaen province to teach people about mental development. The fifth was public assistance such as establishment of religious buildings by Sangha in the Nampong district, Khon Kaen. The sixth was public aids such as the establishment of Sangha Mental Development and Narcotic Freedom Centre at the Nampong district, Khon Kaen province, in order to help more than three thousand habit-forming men within five previous years.

            About the effect of ecclesiastical administration on people in the Nampong district, it was found that it covered five important aspects. The first was administration covering six projects to grow the qualitative development of Sangha—the elder monks development project, the project of monk cremation aids, the project of ecclesiastical officers cremation, the Nampong monk council project, the Thai culture conservation project, and the environment conservation project. The second was education and educational aids—establishment of a Buddhist meritorious school, the establishment of Sunday Buddhist Study Centre, collection of thirty scholarships (300-500 baht for each scholarship) for students, and management of religious education—Dhamma and Pali for monks and novices in two big schools:  Wat Bannongkung School and Wat Chaisribansiaw School. These religious schools maintained a lot of students who passed the examination in each year. The third was the Buddhist spread. There were more 3,000-5,000 people who participated in various activities like a project of moral instruction, and annual spread of Buddhism held by Sangha at the Nampong province. The fourth was public assistance. Sangha at the Nampong district paid more fifteen million baht per year to establish public buildings. The fifth was public aids. Sangha donated two million baht to support educational institutions, governmental institutions, and communities such as equipments given to the Nampong hospital and wanted things given to people who faced natural problems.