Taking the Wei River Basin (mainstream) as a case, a dynamic model of man-land areal system has been established using SD method and Vensim PLE software and taking utilization of water resources as the main clues. Through adjustment of water utilization and pollution index, four scenarios of the simulations during 2005-2025 have been established, which are the high-speed economic development mode, the water-lack feedback mode, the water-lack and environment-pollution feedback mode, and the water diversion coupling mode. The results show that, firstly, system dynamic model is a very useful tool for simulating the man-land relationship in a river basin. It is quite easy to reflect the characters of nonlinear relations, feedback and changeability of the system. Secondly, based on the analysis of the four scenarios, it can be concluded that the economic development is the fastest in the high-speed economic development mode, however, the burden of ecological environment will aggravate, as well as the water, social and economic conditions will get worse sharply. Social and economic developing speed can be regulated by water resources bearing capacity in the water-lack feed back mode, but in some degree economic development will be limited. The water resource limitation and environment pollution are considered in the water-stortage and environment-pollution feedback mode, in which the social and environment development is the slowest. This mode can improve the conditions of water stortage and environmental pollution in a short time, while the slow economic development will suppress the capital accumulation, and will also aggravate the man-land contradiction. The water-lack feedback mode and the water-lack and environment- pollution feedback mode are the supplement of the high-speed economic development mode. The water diversion coupling model diverts water resources into the Wei River Basin, by which the situation of water shortage can be improved, also the economic development can keep increasing at a sustainable high speed, and it is an effective way to balance the man-land relationship in the Wei River Basin. Therefore, in order to make decisions more reasonably, it is important for the government to consider the overall development of economy, resource and environment in decision making.