Abstract: A space-time compensation method, which mitigates the range dependence of ground clutter for the side-looking airborne radar was proposed. By using the specific structure of the space-time steering vector of the clutter, the proposed method was arranged to mitigate the range dependence of both the main-lobe and side-lobe clutter. The simulation results show that, the proposed method can compensate non-stationary distribution of ground clutter, improving the performance of the space-time adaptive processing (STAP).