Changes in the cultural ecology in the Sankara Khiri-Budo Mountains were a comparative study in the locality of two communities: an old village in Budo Valley and a new community at a pier on the Saiburi River. The objective of this investigation was to examine ecological changes and natural resource management and how these changes affected the livelihoods and adaptations of the Malay Muslims residing in the plains of the central Saiburi River. The data were collected, analyzed and opinions were shared with local residents and academics. It was found from the comparative investigation that the Muslim community at Choeng Khao Village in Srisakhon District was a newly-established community composed of migrants from Saiburi District in Pattani Province and from Kota Bharu in Kelantan, Malaysia. They had a relationship with the Sakai ethnic group in exchanging for forest products. The residents had an important center for exchanging goods and cultures as well as migration of people of different ecological and geographical conditions. As for Tanod Village of Ruesoh District, it is a community with a long historical background due to local beliefs and the feudal system in the past. Intra-relationships among the villagers were relatively high as seen from the practice of Dusong communal orchards and rubber plantations, which were integrated farming practices that reflected their ability to be self-sufficient. Nevertheless, the villagers had a trade relationship with villagers in Pha Pu Ngor Village as well. An important discovery about the unique aspect of the study area was that there was a steady economic growth in the two communities and knowledge of single crop cultivation had been transmitted even before the arrival of the national economic development plans in the area. A significant factor for the move was a cultural aspect of the Muslim society that put the priority on kinship and their religion which made the villagers lose control over the management of assets and resources to the state in terms of resource exploitation and ownership. Furthermore, the practice negatively affected the livelihood of the Sakai ethnic group residing in the Sankara Khiri Mountain. Villagers in the two communities took up a new business, that is, rubber wood trading. The trade brought about economic disparities in the Muslim communities because the villagers were unable to adjust to the trading practices and income distribution was not spread evenly.