Abstract: Main-lobe jamming is an important jamming pattern faced by radar in modern electronic warfare. In multiple-radar system, the received jamming signals in different receiving stations would be highly coherent due to the wide beam of jammer. However, the received target echoes are independent because of the random fluctuation of target radar cross section (RCS) with the variation of view angle. According to this fact, this paper proposes a main-lobe jamming suppression method based on the amplitude ratio feature. After the time alignment of each receiving station is performed, the time domain signal is converted into the amplitude ratio feature domain by making the amplitude ratio of the echo signals at each time point. In this feature domain, jamming signals would be "smoothed" in the background due to its correlation, and targets would be "highlighted" due to the independence of the target echoes. Finally, in the amplitude ratio feature domain, the target is subjected to constant false alarm detection with a fixed threshold. Simulation experiments show that the proposed method can effectively suppress the main-lobe jamming and improve the target detection performance under the main-lobe jamming condition.