Abstract: A new experimental technology for testing the aerodynamic performance of near space propeller by a railcar on the ground is proposed,in which the advance speed of the propeller is controlled by a high accuracy railcar,and the rotation speed of the propeller is controlled by a servo-electromotor.According to the equal Reynolds number and equal advance ratio similarity criterion,ground experiments including thrust and torque measurement were carried out to inves-tigate the designed near space propeller aerodynamic characteristics at different flight altitudes, and the experimental data was compared with computational results by strip theory and CFD method.The results indicate that:(1 )because the Mach number at the tip of the propeller is lower,the equal Reynolds number and equal advance ratio similarity criterion is appropriate for the designed near space propeller experiment on the ground;(2 )the ground experimental data of propeller at different altitudes agree well with computational results,and thus it is proved that the new experimental method is feasible and can provide a reference for similar propeller tests.