In this paper, the time reversal (TR) technique is extended to localize a partial discharge (PD) source in the acoustic regime. The proposed acoustic TR method consists of three steps, a) the acoustic waves emitted by the PD source are recorded by at least one sensor, b) the recorded signal(s) are reversed in time and back injected into the considered medium via numerical simulation, and c) an appropriate criterion is applied to identify the focal spot, which corresponds to the PD source location. We present a numerical validation of the proposed method in which the acoustic wave equations are solved numerically using the two-dimensional (2D) finite-difference time-domain (FDTD) method. The minimum entropy criterion is used to localize the PD source. The numerical results reveal that the proposed acoustic TR method is very efficient in localizing the PD source in the presence of the transformer windings.