Abstract: The journal impact factor has been one of the most important indexes for science policy makers to evaluate the research outcomes of researchers or academic staff. However, because of the wide variation in impact factors across field, the impact factor value in one field is not comparable with the other one. It is necessary to standardize the impact factor when we need to compare the journals across field. Five standardization methods were introduced in this paper. Two of them were chosen to be compared with each other using the data from Annual Report for Chinese Academic Journal Impact Factors (2015). The standardization procedure based on journal rank was suggested to be a relatively fair method.