According to the different branches of citypsilas intersections and the traffic flow at different times, the program of intelligent traffic light controller based on VHDL is given and simulated by Quartus II by using hierarchical design thought. The simulation results show that the intelligent traffic light controller can realize the transition of 2-phase, 3-phase and 4-phase based on actual situations. The adaptability and applicability of the system can be strengthened by changing the phase.