This letter proposes a behavioral model for analyzing the ground current in medium-voltage (MV) inductors. The impedance between the terminals and the ground connection of inductors is measured by the impedance analyzer, which is capacitive at low frequency. In order to characterize this impedance, a multistage paralleled RLC circuit is proposed. An analytical method is further developed to calculate parameters of the proposed equivalent circuit, which enables to predict the time-domain response of the ground current in MV inductors. A digital twin of the double-pulse-test setup is developed in LTspice, where the simulated ground currents show good agreements with the experimental measurements.