In the traditional post-Doppler adaptive processing approach, one-pulse channel is used in the temporal filter and the sidelode clutter can be effectively suppressed, while the performance of the suppressing mainlobe clutter is poor. To address these issues, a space-time processing method based on temporal adaptive finite impulse response (FIR) filters is proposed. This method firstly designs a set of adaptive FIR filters, and then an adaptive Doppler filtering operation is performed to the output data of each column subarray. Finally, adaptive beamforming is applied respectively to process the output corresponding to the same Doppler filter. Simulation results show that the proposed method is superior to the 1DT method. In addition, the performance of proposed method is robust in the presence of the array amplitude-phase error.