The invention relates to the research based on an urban road transport intelligent traffic light control system, and provides a system which comprises an image data acquisition circuit, a DSP (digital signal processing) analysis and processing system, an I/O (input/output) extension unit, a driving array and a signal light display unit. The functions such as image A/D (analog to digital) conversion, image analysis and processing, real-time image display and time sequence control are realized by adopting a DSP chip. By analyzing and processing video images, vehicles in different shapes, structures and colors are accurately identified, quantities of static vehicles on the left-turn road, the straight road, the right-turn road and the roadway of a crossroad or the occupied length of the static vehicles are identified instantaneously, and corresponding green light time duration is determined according to the quantities of vehicles on different lanes. A DSP technology is for the first time applied to the intelligent traffic light control field, control on traffic lights through a remote network and intersection single points is realized, the traffic signal light time control period can be regulated and controlled, and the system has positive practical significance in improving traffic capacity and reducing traffic accidents.