Abstract: The ultimate objective of studying the path of investment decision on petroleum exploration and development is to avoid risk and select a correct investment direction, arrange the rational investment scale and ensure sustained, safe supply and sustainable development of petroleum resources of petrochemical enterprises and raise the competitive ability of the enterprises in light of the principle of profit maximization and considering the social objective. The project of petroleum exploration and development has obvious real option characters and the traditional NPV method has not met the requirements for the assessment and decision making of this kind of project. Based on the actual conditions of Sinopec and from the corporative and social objectives, this paper propose a new path of investment decision on petroleum exploration and development, thus enriching the thoughts and methods about the decision on project investment.