The invention provides a system for intelligently controlling traffic lights through decibels. The invention also provides a method for intelligently controlling traffic lights through decibels, based on the above system. The system for intelligently controlling traffic lights through decibels, and the method thereof can acquire the current noise through a noise measuring unit, can determine the current road condition through the noise condition, and can start a new traffic signal light change scheme when the estimated road condition is crowded, so that jam of a crossing can be eliminated and the pressure of traffic polices can be reduced.