An LC composite component includes a magnetic substrate with magnetism, a magnetic layer with magnetism, inductors, capacitors, and core parts with magnetism. The magnetic substrate includes a first surface and a second surface on a side opposite to the first surface. The magnetic layer is disposed to face the first surface of the magnetic substrate. The inductors and the capacitors are disposed between the first surface of the magnetic substrate and the magnetic layer. The core parts are disposed between the first surface of the magnetic substrate and the magnetic layer and connected to the magnetic layer. The thickness of the core part is 1.0 or more times the thickness of the magnetic layer, the thickness of the magnetic substrate is 1.0 or more times the thickness of the magnetic layer.