The most type of propeller used in medium/small UVA with piston motor are two blades and fixed angles. The root and tip of this propeller is wider, and the mid part is narrow. But the rotate speed is higher and flight speed is lower in cruising condition, and the thrust is smaller in the step of taking off after using this propeller in fact. It is nor better for UAV developing in future. Therefore, Several types of propellers are designed for the same UAV platform with the same piston motor in this paper. The capabilities of these propellers in zero velocity and in cruising velocity are tested in NF-3 wind tunnel. According to the analyse of test data, the type of propeller with rectangular blade is better than others in efficiency, thrust coefficient and power coefficient, and especially its rotate speed is smallest in the same power imported, So, this type of rectangular propeller is very fit for the medium/small UVA with piston motor.