In this paper, it is researched the cooperated R&D problem in new petrochemical product development for petrochemical enterprise. Based on game theory, a cooperated R&D game theory is established. Given the payoff matrix and the strategy set of this model, and it is analyzed the game process of the two players and the dominant strategy. For the reasons of high development costs, great failure loss, individual limited rationality and lack mutual trust, this dominant strategy cannot be achieved in practice. This paper also provides us a pattern for analyze the cooperated R&D between enterprises and institute.