In this paper, we present a numerical simulation method of electromagnetic (EM) fields induced by a moving ship (EMFMS), which consist of both the shaft-rate EM field and the static EM field. The shaft-rate EM fields in the frequency domain are first obtained by solving the partial differential equations together with suitable boundary conditions, and then they are transformed into the time domain by using the inverse Fourier transform. Finally, the static fields are added to obtain the EM fields of a moving ship. The effects of the source current intensity and the source position on the EM fields of a moving ship are discussed in detail. A field example of EM response of a moving ship is presented and its characteristics are analyzed.