A common mode choke coil includes a core having a winding core part and a first and second wire wound around the winding core part. The winding core part has a first winding region, a switching region and second winding regions in this order along the axis of the winding core part. In the first winding region, each turn of the first wire is located closer to a first end portion of the winding core part than the corresponding same-numbered turn of the second wire. In the second winding region, each turn of the first wire is located closer to a second end portion of the winding core part than the corresponding same-numbered turn of the second wire. The number of turns of the first and second wires in the first winding region differs from the number of turns of the first and second wires in the second winding region.