Embodiments of the present disclosure are directed toward a molded composite enclosure for an integrated circuit (IC) assembly. In one embodiment, an enclosure for an integrated circuit (IC) assembly may include a molded lid structure having a body portion, and a side portion that extends from the body portion and forms a cavity configured to house the IC assembly, wherein the body portion and the side portion share a contiguous interior material comprising a polymer and share a contiguous exterior material comprising a metal, the contiguous interior material having an opening formed in the body portion such that the IC assembly can be thermally coupled with the contiguous exterior material through the opening. Other embodiments may be described and/or claimed.