The noise filter includes a first capacitor that is mounted on a substrate, and includes one end connected to a live side of an AC line of an AC voltage supplied from an AC power supply, a second capacitor including one end connected to a neutral side of the AC line, a first ground pattern to which another end of the first capacitor is connected, and a second ground pattern to which another end of the second capacitor is connected. The first ground pattern and the second ground pattern are not connected electrically on the substrate.