In the design of power plant and substation grounding, as China’s electric standard DL/T 621-1997 has been adopted by domestic design institutes for a long time, which has big differences in the design method and principles with the IEEE standard, it has arosed great difficulty in the electric design work for overseas projects. Based on the review of the relative domestic and foreign grounding standards and literatures, the differences and similarities between these two standards are compared from three aspects: the choice of grounding conductor section, the grounding resistance, as well as the required value of step and contact voltages. Then the characteristics and calculation methods of these two standards in these three aspects are presented and discussed. Furthermore, through analyzing and derivating the calculation formulas listed in the two standards, some useful conclusions of grounding design and calculation for overseas power projects are proposed.