A method for jamming airborne SAR radar implemented by a jamming device includes at least two cooperating units surrounding an area on the ground to be protected, at least two units providing a radar-detection function and at least one unit providing a radar-jamming function, each unit being interlinked by a two-way data link and being synchronized by a common clock, the method comprises a step of identifying the signals received and whether the received signals correspond to SAR signals; a step of characterizing the received SAR signal over a short duration; a step of computing a filter adapted to the signal; a step of carrying out pulse compression of the signal; a step of iteratively periodically characterizing the signal over a long duration; a step of computing the jamming signals to be transmitted; a step of transmitting the jamming signals.