In the study of Changes in the Productive System from Consumptive to Commercial and Their Effects on the Khamu Way of Life: A Case Study of Ban Phu Kam, Tambon Ngob, Amphoe Thungchang, Nan Province, it is found that there are 2 factors that cause changes in the productive system: the external factors are the influence of external marketing and economic system and transportation improvement, and the internal factors are pressure on land utilization and changes in ecological surroundings. These factors have pushed the Khamu in Ban Phu Kam to find solutions to the problems in the community with the cultivation of a new commercial crop which is orange. Because the revenue from the product makes the orange farmers have a higher economic status, the people in the community tend to cultivate more oranges. The results of orange cultivation are changes in the production system from a consumptive to a commercial system and the effect on the community is that the farmers have to be bound and dependent on the marketing system. The labour system has also changed; from the exchanging of labour or Au Mue (Au Rang), which has decreased, to the hiring of labour. There are also modern agricultural methods and, permanent land utilization along with shifting land utilization. As for beliefs, it is found that no beliefs are related to production as in the past because of the changes in production. Furthermore, commercial production is a factor that causes the relationships of the people in the community to fail because they do not have enough time to attend community activities, so it leads to misunderstandings among the members of the community and leads to social conflicts finally.