The invention discloses an anti-main lobe deception jamming method for a waveform diversity array radar, and mainly solves the problem that an existing radar has difficulty in suppressing main lobe deception jamming. According to the technical scheme, a waveform diversity array emits a stepped-frequency signal; after received echo data is subjected to filter matching, distance space-varying compensation is conducted in a transmitting-receiving two-dimensional domain; based on the subspace projection technology, a main lobe direction subspace is constructed and received, an echo signal power in the main lobe direction is obtained, and a power detection method is used for interference sample selection; according to a selected training sample, the adaptive or non-adaptive beamforming technology is used for calculating the beamforming weight, the weight is used for filter matching of the compensated echo data in the transmitting-receiving two-dimensional domain, and inhibition of main lobe deception jamming can be achieved. The method reduces the system complexity, saves platform resources, improves the estimation performance of an interference covariance matrix, improves the anti-jamming ability of the monostatic radar, and can be used in electronic countermeasure jamming.