Abstract: During the navigation of ship formations on the sea surface, interference devices are often deployed to ensure their safety. To investigate the anti-jamming performance of passive millimeter-wave imaging technology against such interference devices in maritime target detection, a three-dimensional scene modeling of the sea surface target group, which includes ship formations, typical interference devices, and the sea surface environment, was first conducted. Passive millimeter-wave imaging simulation at W-band of the entire scene was performed using the brightness temperature ray tracing method. A detection method specifically designed for ship target groups and their core high-value targets was proposed. The superiority of the proposed method over existing methods was quantitatively analyzed using detection metrics. The simulation results indicate that the brightness temperature distribution of typical interference devices on the sea surface significantly differs from that of sea surface targets, having minimal impact on W-band passive millimeter-wave imaging detection. In the context of maritime target detection tasks involving typical interference sources, passive millimeter-wave imaging technology can serve as a significant supplementary detection method, providing reliable technical support for maritime target monitoring.