Abstract: A review is given on the current state of and recent progress in the study on the material removal mechanisms of Si wafers during chemical mechanical polishing (CMP). Thus a summary is made on the research progress about the material removal mechanisms of Si wafers subject to CMP and about the chemical mechanical polishing of SiO_2 as the commonly used dielectric material of the Si wafers. At the same time, the current state of and research progress in the chemical mechanical polishing of W, Al, and Cu as the electric-connecting materials of wafers are also summarized, and the chemical-mechanical synergistic effect during the CMP process of SiO_2, W, Al, and Cu is highlighted. It is supposed to introduce atomic force microscopy and electrochemical microscopy into the study of CMP so as to clarify the disputes on the material removal mechanisms during the CMP process and to establish scientific guidance to increasing the CMP efficiency.