Abstract: High\|voltage shielded cables generate induced voltage during EMU electrical system operation. The shielding layer needs to be properly grounded to ensure vehicle safety and reduce external electromagnetic radiation from cables. Taking the transformer secondary winding cable as an example, the EMU grounding system is introduced. Starting from the mechanism of induced voltage on the shielding layer, the principle of single\|ended grounding of high\|voltage cables shielding layer is analyzed, and the grounding structure of the cable shielding layer is proposed. Induced voltage value of the shielding layer under reliable grounding and poor grounding conditions is compared through experiments, which verifies the reliability of the grounding structure.