The exposure risk of magnetic fields produced inside high voltage substation is still challenge issue for both utility design engineers and biomedical researchers as well. There are two different types of exposure; the first type is the public which comes from any temporary human presence nearby any electrical utility installation while the second type is the residential which comes from any type of resident or semi-permanent presence for more about 8 hours (working shifts) nearby any electrical utility installation. This classification is mainly dependent upon the levels and durations of exposure. This paper presents the full simulation for two typical high voltage substations of 500/220 kV and 220/66 kV with different bus bar configurations for calculating the magnetic field distributions. The effects of different bus bar configurations on the magnetic field levels are presented. The simulated results are compared with measured values to validate the accuracy of simulation.