The rise of the low-altitude economy has led to the widespread adoption of small unmanned aerial vehicles (UAVs) in logistics, surveying, and entertainment, yet the associated security risks have grown increasingly prominent. Detecting low-slow-small (LSS) targets is therefore crucial in domains such as national security, airspace regulation, and UAV defense, as it effectively mitigates potential threats posed by small and low-altitude flying objects. In response to limitations of current sensors with regard to cost-effectiveness, operation under complex lighting conditions, and broad field-of-view coverage, this paper proposes an LSS target detection system that leverages both an event camera and an RGB camera. First, the high-speed imaging and wide dynamic range of event camera are employed for an initial “sweep”, and an event-based detection algorithm provides preliminary target localization. Next, an information collaboration module fuses the two-modal data to enhance detection accuracy. Finally, the high-resolution and dynamic zoom features of RGB camera enable a “gaze” mode, combined with a dedicated image recognition algorithm for fine-grained target identification and tracking. Under complex lighting and wide field-of-view scenarios, this system achieves both low cost and high performance, offering an effective new approach to LSS target detection.