Abstract: The automotive industry is an important source of China's energy consumption and pollutant emissions, and is the focus of the work of energy saving and emission reduction, and the government adjusted auto consumption policy to encourage and guide automotive consumer s' buying behavior. In this context, according to the game between the situations in China's auto consumption market consumer buying behavior of different cars and government consumption policies, an evolutionary game model of consumer purchase behavior for different displacement cars is constructed, and the evolution problem of the evenly mixed consumer group's different displacement automobile behavior is analyzed in the case of single automobile brand. Studies have shown that: in the combined effect of oil prices, consumer utility, consumer policy and car costs, consumer buying behavior exists to the three specific evolution cases of the evolution to the small displacement evolution, random evolution and the evolution to the large displacement. Then the evolution characteristics of consumer buying behavior are analyzed in the particular case of the Volkswagen Magotan car in the current circumstances. When the operational costs for lower oil price is not enough to become an obstacle to the car consumers to buy cars behavior capacity factors, or the utility consumption difference is higher, the government should increase the intensity of consumption policies to guide consumers to purchase low-emission cars; when the oil price is on the higher level, the government can gradually relax implementation auto consumption policy. The theoretical support is provided for the government to guide automotive consumers' scientific and reasonable energy-saving buying behavior.

Key words: buying behavior, evolutionary game, consumption policy, utility of consumption, energy conservation and emission reduction