Abstract: Beamforming is a commonly used noise source localization method in engineering, but the sidelobe level of its sound source localization results is greatly affected by noise, leading to reduced accuracy in low signal-to-noise ratio (SNR) conditions. To address this issue, this paper proposes a beamforming method based on block cross-correlation. The method processes the measurement array by dividing it into blocks, separately calculates the focused sound field of each block, and then computes the cross-correlation of the focused sound fields from different block divisions to reduce the influence of noise on the sidelobes in the sound source localization results. Numerical simulation results show that, compared to conventional beamforming methods, the proposed method can improve the dynamic range of sound source localization results by more than 10 dB and achieve low-sidelobe sound source localization at a low SNR condition of −5 dB.