Current field calculation based on the resistance network method (RNM) and temperature field calculation based on the finite volume method (FVM) can be used to evaluate the performance of high-voltage direct-current (HVDC) grounding electrodes. The main idea of the two methods is to transform an electric and temperature field problems to equivalent circuit problems by dividing the 3D soil space near the grounding electrode into a suitable number of contiguous and non-overlapped cells. Each cell is represented as a central node connecting to the adjacent cells. The resistance network formed by connecting all the adjacent cells together can be solved to calculate the current field. Under the same conditions, the results calculated by the RNM are consistent with the result by CDEGS, a widely used software package for current distribution and electromagnetic field calculation. Based on the finite volume method, the temperature field results are also calculated using time domain simulation.