Abstract: In the experimental study of water flood remaining oil, a new similarity transformation method was currently developed. In the different displacement models with the same core, the same fluid properties, and the proportional geometric dimensions, equal velocity (real speed) was adopted to obtain the pump displacement and the remaining oil distribution and exploitation performance are similar. This law is the core law in the paper, it can be effectively applied to the physical model experiment on the study of re-maining oil distribution. In order to verify the accuracy and practicability of this method, this paper designs more than 20 numerical simulation schemes to research. Conclusions obtained from data analysis:remaining oil distribution and exploitation performance between models conversed by equal velocity similarity method has better similarity, and experimental operation is relatively simple and has strong practicability.