Abstract: During the period of enhanced transition,there have been an increasing number of cooperative innovations between asymmetric corporations which are in different industries or have different scales and strength.However,many cases have shown that it is difficult to maintain a longterm and steady relationship of cooperative innovation between asymmetric corporation participants.The relationship of cooperative innovation often collapses along with one participant breaking the contact unilaterally.To solve this practical problem,we propose an evolutionary game model in which the participants are assumed to have bounded rationality.The proposed model has advant ages over traditional game theory's assumption of full rationality by taking the following four factors into account: excess returns of cooperative innovation,additional revenue of breaking the contact,coefficient of excess return's distribution,and cost of breaking the contact By const ructing game model of two asy mmet ric corporations which are in different indust ries or have different scales and strength,this paper analizes the strategies of cooperative innovation under the evolutionary game theory,the evolutionary stability of strategies and the asymmetric corporations' decision strategies.It is shown that,if the corporation's additional revenue of breaking the contact is greater than t he excess ret urns of cont inuous co operat ive inno vation,t he st rategy choice of cor porat ion will depend on the probability of the other corporation' strategy,but cooperative innovation will eventually terminate because of one corporation' breaking down the contract.On the contrary,cooperative innovation will be maintained because of two corporations' complying with the contract.The corporation's decision making is affected by the revenue of its strategy before cooperative innovation and by the probability of the other corporation's strategy in the process of cooperative innovation.

Key words: asymmetric corporations, period of enhanced transition, cooperative innovation, evolutionary game