During the installation and maintenance of GIS equipment, DC voltage drop method is needed to measure the resistance of the GIS circuit in order to check the connection status of circuit breaker, disconnecting switch and other equipment. However, DC voltage drop method needs to remove the grounding wire when measuring, which is cumbersome and inefficient. At the same time, this method may damage the structure of GIS equipment and induce high voltage from the surrounding charged equipment. Therefore, based on the topology of GIS equipment, a fast measuring method of GIS circuit resistance without removing the grounding wire was proposed in this paper. The GIS network was extracted into a multilevel T-type impedance network, and the corresponding impedance matrix was established through the node voltage equation and the loop current equation. The impedance matrix is solved by applying DC excitation sources of two kinds of wiring schemes. And the influences of earth network shunting and three-phase interphase shunting on the measurement were analyzed, and on this basis, the scheme of applying excitation source was proposed. After validating, the measurement results of proposed method were similar to DC voltage drop method. This method can improve working efficiency. It has reference significance for measuring circuit resistance of the same type of GIS equipment.