To solve the policy problem between transportation and environment in trade-offs, above all, it is necessary to understand the complicated relationship between transportation and environment clearly before selecting policy alternatives. From this point of view, this study will propose the logic structure to examine the complex interaction of transportation and environment and investigate theoretically what kinds of impact would appear by the air related polices. In this research, we used ’system-dynamics’ which investigates the complexity through the flow of information and materials and the interaction of elements, which constitutes systems. System Dynamics is an approach that the variables to decide structural relationship in a system affect one another not in only-way but in inter-way and the power of influence changes time by time. This research is trying to examine the complex interaction of transportation and air pollution. For achieving this purpose, causal maps in System Dynamics approach were used. The main issues are as follows; first, to investigate the dynamic relationship between transportation and air pollution caused by exhaust emission gas. Second, to structuralize the logic of simulation to experiment the impacts of policies to relieve air pollution.