Real estate hedonic price model is applied to determine the average sale unit price of newly built housing projeer. In order to solve the problems of the lack of sample and the high correlation of some of the housing characteristic factors with each other in this application, a housing project hedonic pricing model based on principal components analysis of housing characteristic factors has been established. Through a case, the author has analyzed the economical significance of the implicit prices. With the model, the average sale unit price of a newly built housing project can be determined by rule and line.