This paper presents a new procedure for tracking the source location of voltage sags in a power system. In the proposed method, the power quality meter locations are firstly determined based on the sensitivity of the system fault current level to the faulted voltage. Then, a current deviation index for representing the variation of each branch current before and after the disturbance is calculated to find the location of the voltage sag source. To illustrate the usefulness of the proposed method, the IEEE 30-bus benchmark system is under test. By observing the results, it shows that the proposed method is efficient and accurate to track the source location of the voltage sags.