Transportation is a sector with high energy consumption as well as high emissions. Generally speaking, economic growth will inevitably lead to the increase of travel demand and vehicle population, which in turn results into the augmentation of environmental and social costs. For metropolis like Beijing under rapid development, there exist various possibilities and options for transport development policy instruments. But there is no guarantee that they will be suitable for Beijing, although they are effective in their local places. This article assesses what kind of policy can most effectively improve the traffic conditions in Beijing in the future. After literature reviews on the practices of foreign policy and we established several feasible scenarios. Then, we used the Long Range Energy Alternatives Planning System (LREAP) analyzed their corresponding results of reduced energy consumption and emissions. Finally, by simulating and computing the realistic Beijing transportation scenarios, this paper scientifically assesses what kind of policy can most effectively improve the traffic condition in Beijing in the coming decade.