This study aimed to demonstrate the evaluation of traffic emission control plans based on the group decision–making model. The model assigned values in the form of grey interval linguistic variables because of the uncertainty in their multiple attributes to create a group synthesis decision matrix. The optimal plan could then be determined by calculating the possible degrees of every plan that could define the ideal situation. The model could effectively deal with inaccuracy due to the uncertainty and multiple attributes of emission control plans compared with the existing studies. It ensured scientific and rational decision-making in the management and control of traffic-related emissions. Finally, four different emission control plans in a certain city were compared to verify the effectiveness of the model via a numerical example.