The invention provides a self-adaptive tidal lane and crossing transition system based on LED traffic signs and a control method. A traffic flow information acquisition device C collects real-time traffic flow data, and sends the traffic flow data to a lane division analysis and calculation device H; then, the lane division analysis and calculation device H carries out analysis and calculation to obtain a real-time lane division scheme, and the scheme is sent to a display control device X; and finally, road markings LMB and crossing guidance sign display LKX display a road clearing process and the lanes and crossings obtained after transition. The system realizes self-adaptive dynamic lane switching according to the traffic flow information. The self-adaptive tidal lane and crossing transition system, compared with the manual transition mode, accords with the idea of intelligent traffic better, so that the problems of tidal lane crowding phenomenon and crossing traffic flow concentration can be solved to the largest degree, and energy is saved and discharge is reduced.