The analyses of the tourism resources,traffic,service facilities and the tourist quantity of Shanghai and some other cities in Yangt se River Delta bring forward that cooperation can offer the involved cities comple-mentary resources.Simultaneously,because benefits and competition exist among those cities,the unity will not be kept forever. Although founding organization and signing cont ract can make the unity st rong,keeping faith ,and profitabie between cities,yet the imbalance of information is not considered.Bring the game theory of coop-eration and competition to this domain,advance that the competition among the cities can not be ignored while the unity has been founded.Using the KMRW model and Pareto improvement to solve the competition problem behind the cooperation,suggests establishing"reputation information system".