A method for bonding a heat sink to a chip package structure is disclosed. The chip package structure at least comprises a chip and a stiffener ring around the chip. Both the chip and the stiffener ring are set up on a substrate. The heat sink comprises a first protruding section located at a position corresponding to the chip and a plurality of second protruding sections located at positions corresponding to the stiffener ring. The method includes forming a gluing layer on the first protruding section and the second protruding sections of the heat sink and pressing the heat sink against the chip package structure to bond the heat sink and the chip package together. The first protruding section of the heat sink is attached to the chip and the second protruding sections are attached to the stiffener ring.