Abstract: Synthetic aperture radar (SAR) has a wide application prospect in the field of sea observation and maritime ship detection. The multi-channel interferometric SAR technology can reduce the interference of clutter in the background. The dual-channel structure of the ΣΔ-beams SAR can be easily applied to the existing radar system. On the basis of both the two-dimensional sea clutter model and its SAR echo model, this paper proposed a sea clutter suppression method based on the ΣΔ-beams interferometric SAR. First, sphere-invariant stochastic process (SIRP) is used to simulate the amplitude distribution of the two-dimensional correlated K-distribution sea clutter. Then, the echo simulation and suppression of sea clutter is studied in the ΣΔ-beams interferometric SAR system. Adaptive clutter suppression interferometry (ACSI) is proposed to realize the detection of ship targets in the presence of inter-channel unbalance and the special properties of sea clutter. Finally, the computer simulation results verify the correctness and feasibility of this method.