<p>Differential beamforming (DBF) has attracted much attention due to its ability to achieve high directivity factors (DF) with limited array apertures. However, this beamforming technique remains highly sensitive to sensor self-noise and array errors, making it challenging to enhance the algorithm’s resistance to interference while maintaining its robustness. This paper proposes a robust differential beamforming algorithm based on sparse optimization to address this issue. The algorithm fully uses the two-stage cascade structure of the filters to design the differential beamformer flexibly according to the target requirements. After forming a low-order differential beam pattern using the first-stage subfilter, the second-stage filter introduces amplitude response constraints and sparse constraints under the criterion of maximizing white noise gain (WNG). This ensures that the main lobe of the beam pattern consistently points toward the target direction and attenuates the beam response in the interval of the possible interference range as much as possible. This method effectively solves the problem of amplification of the sidelobe in the beam pattern of the second-stage filter within the cascade structure, so that the energy can be better concentrated in the main lobe under the beam pattern product theorem, which ultimately improves the interference immunity and DF of the algorithm. Simulation results illustrate the effectiveness of the proposed method.</p>