An in-vehicle inverter device includes a noise reduction circuit, which has a common mode choke coil configured to reduce common mode noise and normal mode noise contained in DC power, and an inverter circuit, which receives the DC power in which the noise has been reduced. The noise reduction circuit includes: an input-side capacitor and an input-side resistor provided on the input side of the choke coil; an output-side capacitor and an output-side resistor provided on the output side of the choke coil; a first filter circuit that includes the choke coil, the input-side capacitor, and the input-side resistor; and a second filter circuit that includes the choke coil, the output-side capacitor, and the output-side resistor. The first and the second filter circuits reduce leakage noise generated in the inverter circuit.