Composite electronic component

A composite electronic component comprising:

• first and second wiring structures;
• an insulating layer positioned between the first wiring structure and the second wiring structure;
• and
• an electronic component embedded in the insulating layer,
• wherein the insulating layer includes a first insulating layer having a first surface and a second insulating layer having a second surface that partially contacts the first surface,
• wherein the second insulating layer is made of a mixture containing at least a binder resin and filler,
• wherein the electronic component has a main surface covered with the second insulating layer, a back surface positioned on an opposite side of the main surface and contacting the first surface of the first insulating layer, and a side surface connecting the main surface and the back surface,
• wherein a fillet of an adhesion layer made of a same resin material as the binder resin contained in the second insulating layer at a corner formed by the first surface of the first insulating layer and the side surface of the electronic component is formed.