The invention discloses a control device for public vehicles passing through crossroads, which comprises a signal emitter and a controller, wherein the controller consists of a signal receiving module, a control module and a display module which are connected in series sequentially; and the display module consists of traffic lights, the signal emitter is arranged on a public vehicle, the controller is arranged at the top of a traffic light post, and the transmitting end of the signal emitter is wirelessly connected with the receiving end of the signal receiving module. When countdown remaining time of a green light is smaller than adjusting time and when the public vehicles reach effective parking spots, a driver presses a remote controller to send out delay requirement, and the control device which is a singlechip executes an external interrupt program after a receiving device receives signals; and when the current green indicating light flickers and the countdown stops on the current second to flicker, the countdown is recovered through delaying time. The control device can effectively utilize road resources and improve effective passing amount of roads in unit time.