The invention provides a method and system for photographing the overspeed unlawful act by a video tracking technology. The method comprises the steps that whether a vehicle enters a first identification zone or a second identification zone is judged through the video tracking technology, after the vehicle enters the two identification zones in a front-and-back mode, the speed of the vehicle is obtained according to the distance between the two identification zones and the time when the vehicle reaches the two identification zones, the speed of the vehicle is compared with a speed limit value, and whether the vehicle runs in an overspeed mode is judged. The video tracking technology is adopted to achieve the higher accuracy and real time performance. In addition, according to the method and system, the overspeed running vehicle can be photographed, the vehicle in abnormal parking can be rapidly and accurately detected, the function of the system is stronger, the functions can be achieved through a video tracking unit in the system for photographing the overspeed unlawful act, and the utilization rate of the system for photographing the overspeed unlawful act is improved.