Abstract: Construction contract risk assessment is the most important process of construction project contract management , how to carry out the construction contract risk assessment effectively is one of the important subjects about the existence and development of the construction unit. Based on the theory of contract life cycle this paper established construction contract risk evaluation index system paper through the literature review method, and then by means of correlation functions of structure element, determine the matter-element classical domain, joint domain, establish extenics evaluation model of construction contract risk, analyze and determine the weight coefficient by entropy method in quantitative evaluation of the construction contract risk grade, finally, evaluate X company’s construction contract risk by the model. In short, the objectives of the paper is to provide the theoretical base for the research and application of related field.