Integrated circuit package system with interposer

A method of manufacture of an integrated circuit package system includes: providing a base substrate; coupling a base integrated circuit on the base substrate; forming a double side molded interposer unit over the base integrated circuit including: providing an interposer substrate having an interposer top and an interposer bottom, mounting a first integrated circuit to the interposer bottom and electrically connected thereto, mounting a second integrated circuit to the interposer top and electrically connected thereto, and molding a first chip cover on the first integrated circuit and a second chip cover on the second integrated circuit; and coupling an external component to the double side molded interposer unit.