The present invention discloses a method for generating a microwave predistortion signal and a device thereof. The microwave receiver receives the first receiving signal after ananlog to digit conversion and performs channel compensation for the first receiving signal so as to obtain the second receiving signal,the first transmitting signal is estimated according to the second receiving signal,the first transimitting signal is the transmitting signal before ananlog to digit conversion of the microwave transmitter,the predistortion factor calculation is performed according to the second receiving signal and the first transmitting signal,the second receiving signal before the first transmitting signal is estimated by using the first order factor obtained by the predistortion factor calculation for linear distortion compensation,and the other predistortion factors besides the first order factor are sent to the microwave transmitter to make the transmitted signal of the microwave transmitter perform nonlinear predistortion. The frist receiving signal is the signal after ananlog to digit conversion, namely teh receiving of the first receiving signal does not require the microwave receiver to increase the additional channel that the receving channel of the microwave receiver can be used, thus saving the cost.