Abstract: In order to investigate the simulation method of a scale model for a porous wind screen, the aerodynamic coefficients of vehicles under the action of a wind screen installed on the railway bridges are measured by wind tunnel tests. The wind screen is 2.05m high, with the porosity of 30%, and with different hole shapes. The effects of hole size and hole shape are analyzed, and the similarity between the wind screen with circular holes and the wind screen with longitudinal bars are discussed. The result shows that the circular hole size of a wind screen at the scale of 1∶20 should be in the range of 8mm to 12mm; the hole shape of a wind screen with the same porosity has some certain effect on the aerodynamic coefficients of the windward vehicle; the longitudinal bar wind screen with more than 10 gaps is equivalent to a wind screen with the circular hole size of 8mm. The results could provide some references for the wind tunnel test and numerical simulation of a wind screen.