A adaptive digital predistortion hybrid algorithm of LMS and RLS based on training sequence is proposed, which is applied to a digital pre-distortion system based on polynomial. It can estimation and update adaptive digital pre-distortion filter coefficients. First, This paper was given the configuration of all digital pre-distortion system. Second, adaptive digital predistortion method was realized. A method was simulated by MATLAB software. At last, experimental system was set up and tested experimentation. Simulation results and test results show that wideband power amplifier have better performance based on adaptive digital predistortion method, OFDM power amplifier of linearity is improved 6 dB.