To prevent noise from being routed from a common ground path including bodies to an auxiliary machine circuit, a signal circuit, or the like connected to low-voltage-side winding, in a transformer for vehicles.
A main transformer 3 is suspended and supported by a body 1 through a metallic suspension tool 2. In a winding body 7 in a transformer tank 4, an electrostatic shielding plate 7c is included between high- and low- voltage-side coils. In the high-voltage-side coil of the winding body 7, one terminal is connected to a circuit breaker for opening and closing power from a feeder, and the other is grounded through a ground terminal 8 that is provided at a winding tank section 4b, a ground line 9, a wheel 10, and a rail 11. Then, the electrostatic shielding plate 7c of the winding body 7 is connected to the ground terminal 8 through a ground line 14.