The statistics of energy consumption and carbon emission of building during the whole life have the characteristics of poverty and great fluctuation in China, especially during the preparing stage of building materials. Further, analysis models to predict the energy consumption and carbon emission with high-accuracy and operability have not yet been developed. In the present study, the unequal interval grey model was introduced for the analysis and prediction of the energy consumption and carbon emission of the residential building materials at preparation stage in Hefei City. The test results with sufficient accuracy were obtained according to the posterior-variance-test. An evaluation index selecting the standard coal as the reference was proposed on the basis of the proposed model to express the energy utilization ability under unit carbon emission. The prediction results show that the energy utilization ability of building materials at preparation stage is still much lower, which can be improved considerably by comparing with the reference index. The proposed method can be employed to evaluate the energy utilization carbon emission in other building form as well as the unfinished deserted building and vacant house.