A semiconductor package includes an interconnect structure having a first surface and a second surface opposite to the first surface, at least one optical chip over the first surface of the interconnect structure and electrically coupled to the interconnect structure, an insulating layer contacting the second surface of the interconnect structure, and a molding compound over the first surface of the interconnect structure. The insulating layer includes a third surface facing the second surface of the interconnect structure and a fourth surface opposite to the third surface. At least an edge of the optical chip is covered by the molding compound.