Thailand has a long history of agricultural land policy since the first establishment of the former Kingdom in the 13th century. Most of the early day policy is to manage the land around the capital area. Bangkok Metropolitan Region has been formed to follow agricultural export policy since the 19th century. To explain what has happened to suburban farmland and urban agrarian families is to understand what influences the policy has on land and people. The paper is to review the former agricultural land policies and agricultural support programs of Thailand, and to investigate what could lead to environmental impact and impact on agricultural households as environmental agent. The review found that the export activities along with agricultural support program shaped today Bangkok agricultural land without proper protecting mechanism for farming environment.