PROBLEM TO BE SOLVED: To provide a retainer ring structure for a chemical mechanical polisher.SOLUTION: The retainer ring structure comprises an upper ring of a metal material including a pair of terminal protrusions which are formed naturally on a side face of a central groove part by forming a plurality of bolt holes to be coupled to a head of the chemical mechanical polisher on a top face and forming the center groove part with a fixed depth in a central part; and a lower ring of a resin material with which a coupling groove to which the upper ring is coupled is formed in the center and a central protrusion inserted into the central groove part of the upper ring is formed in a central part of the coupling groove. The ring of the metal material with which the protrusion is formed in the lower part and the ring of the resin material including the coupling groove into which the protrusion is coupled are firmly and easily coupled, thereby increasing a strength of the ring structure and improving a degree of fl
