Red-light violation video detection is one of the critical techniques in the intelligent transportation system, it is superior to traditional detection methods in aspect of function and maintenance. According to the practice of crossroads and the characteristics of vehicles running red-light, this paper presents a vision vehicle detection algorithm based on detection region to detect moving vehicles, and then analysis movement trend for vehicles by processing. The system implements the correct judgment of running red-light with two steps of process above. The experiment results show that the algorithm not only satisfies the real time requirement but also detects red-light violation with a high accuracy.