The water injection pore volume multiple in conventional core displacement experiment is inconsistent with that in the entire reservoir, which results in the difficulty in the application of the results of core displacement experiment to the calculation of reservoir development. Therefore, it is required to know the distribution of water injection pore volume multiple in the formation which is consistent with that in the core displacement experiment. In this study the case of the Five-spot Well Pattern was used to determine the streamline distribution in the formation. Fluids flow one-dimensionally along the streamline and each streamline can be seen as the connection of a number of cores. The flowing resistance on each streamline was measured to determine the water injection rate of each streamline. According to the theory of one-dimensional oil-water two phase flow, the water injection pore volume multiple of each core in the streamline could be calculated. Thus, the consistence would be achieved between the multiple of water injection in core displacement experiment and that in the formation. The research results was of high theoretical and practical significance to the application of the results of core displacement experiment to the research of reservoir development.