The invention relates to an airfield runway foreign object detection system which comprises laser scanning devices, imaging devices, an alarm device, a display device, a control system, and the like, wherein multiple groups of the laser scanning devices and the imaging devices corresponding to the laser scanning devices are provided as well as arrayed and arranged at both sides of an airfield runway; and laser scanning and imaging signals are transmitted to the control system and the display device through transmission lines. In the airfield runway foreign object detection system, the characteristic of high precision of laser is utilized, thus smaller foreign objects on the airfield runway can be detected, and the physical coordinate positions of the smaller foreign objects can be determined; and the imaging devices are used for providing visual and visible image information for staff so as to be convenient for confirming and processing alarm targets for the staff. The system can be used for monitoring the airfield runway around the clock for 24 hours without being influenced by environment, thereby false alarms are reduced. Meanwhile, the system can automatically carry out detection during the period of a regular flight without influencing the normal operations of the airport.