The present application discloses a traffic monitoring device capable of switching camera modes, comprising a sensor group, a infrared camera group, a visible light camera group, a visible light camera head, a infrared camera head, a head driver and a digital signal processor. The sensor group comprises pressure sensor, photoelectric displacement sensor and photosensitive sensor; the infrared camera and the visible light camera collect image information. The above devices are used as the detection front ends connected to the digital signal processor. The head driver adjusts the angle of the visible light camera and the infrared camera in real time. The system described in this application has two working modes: continuous shooting and interval shooting, which shortens the working time of the system, extends the life of the system, and reduces the cost of the system. The shooting camera can be switched according to the light intensity, to avoid the dazzling effect of supplementary visible light on human eyes, and to reduce hidden dangers to traffic safety. The camera angle can be fine-tuned with no dead angle shooting. License plate recognition and illegal shooting can be performed at all weather.