Finite difference time domain method which is one of most powerful numerical solution was introduced by Yee in 1966. By now, it has been widely used in many areas especially in EM modeling. However, in some area, ultra low frequency (ULF) is required such as Sea-bed logging and induction logging cases, EM problems require extremely large number of time steps to get satisfied results. Thus, how to significantly reduce the large time-steps becomes very important in such FDTD applications in ULF problems. In this study, a new method to greatly reduce the total simulation time is proposed and this method will be applied to time domain logging problems.