An LC composite component includes one or more inductors, one or more capacitors, a magnetic layer, and a substrate. The substrate has a first surface, and a second surface opposite to the first surface. The magnetic layer is disposed to face the first surface of the substrate. The one or more inductors are disposed between the first surface of the substrate and the magnetic layer. The substrate has a thickness greater than that of the magnetic layer in a direction perpendicular to the first surface of the substrate. The substrate has a complex permeability having a real part and an imaginary part that are respectively smaller than the real part and the imaginary part of the complex permeability of the magnetic layer.