Aiming at the multi-point grounding fault of the transformer core, the ground current is studied, and a simpler uniform modeling method in practical application is proposed, and the accuracy of the proposed method is verified. Meanwhile, the finite element model of the transformer core multi-point grounding fault is established. In the Maxwell three-dimensional transient mode, the finite element calculation of the transformer multi-point grounding fault is performed, and short-circuit current characteristics of the transformer core under multi-point grounding fault are analyzed.