Eco-problem is the main obstacle which restricts the sustainable development of the regional economy in poor areas.Based on the game theory, different behavior of each economic body is analysized in the process of eco-protection and reconstruction in Xihaigu region of Ningxia Hui Autonomous Region. It is pointed out that the inefficiency of the eco-protection and reconstruction is induced by short-term behavior and interest conflict among economic interest bodies. Furthermore,in order to realize really the win-win type of eco-construction and economic development,harmony mechanism should be established in accordance with every economic interest bodied.