The key problem of integration in Yangtze delta area is benefits allocation and harmonization.Ruhinstein set up a bargain model for offer-counteroffer.The model has three implications,First,it is about discount coefficient；Second,it is about first move advantage and second move advantage；finally,it is about accept principle as soon as.Based on the model,the paper studies the benefits share mechanism of Yangtze Delta area,and thinks that there are two-level behavior main bodies including the government and the firm.It is important for integration of Yangtze Delta area to build the consultation mechanism between governments and co-operation mechanism between firms.