The disclosure discloses a method for non-uniform sampling of a singularity point of a multi-channel Synthetic-Aperture Radar (SAR) system. The position of a singularity point is determined and rejection of data is performed for raw echoes of multiple channels. According to a frequency-domain reconstruction filter algorithm, data remained after the rejection are reconstructed to obtain a reconstructed echo signal and imaging is performed to obtain a first image. Rejected data are reconstructed according to the frequency-domain reconstruction filter algorithm to obtain a reconstructed echo signal, imaging is performed to obtain a second image, and the first image and the second image are superimposed to obtain a third image. The disclosure further discloses a device for non-uniform sampling of a singularity point of a multi-channel SAR system. The technical solution of the disclosure can solve the problem of a frequency-domain reconstruction filter failure caused by a singularity point and obtain a higher image Signal to Noise Ratio (SNR) through image compensation.