Abstract: According to the propeller Reynolds-similarity theory and the plasma induced jet similarity theory,the method which is used to study the performance of plasma flow control of high-attitude propeller by ground experiment is put forward based on the blade element theory. First,the propeller geometry and motion parameters are converted to the inflow velocity and an-gle of attack on the blade element.Second,the induced plasma voltage and inflow parameters are determined based on the similarity theory in ground experiment.Finally,the collected experi-mental data is processed to assess the aerodynamic performance of propeller.A high-attitude 20km S1223 airfoil propeller plasma flow control experiment is conducted by this method.It is found that when the propeller revolves at the speed of 300r/min under forward velocity of 5 ~20m/s,the thrust of propeller is increased by 6.6%~10.9% with the high voltage AC input, but at the speed of 600r/min the thrust is reduced by 0.52%~1.7%.