Abstract: Single crystal SiC has become an important epitaxial layer material because of its excellent physical and chemical properties.It is widely used in satellite communications, integrated circuits, and consumer electronics.The growth of an epitaxial layer of SiC wafer requires an ultra-smooth, flat surface with low process surface damage and residual stress on the single crystal SiC surface.The surface quality determines the subsequent epitaxial layer quality and ultimately affects the performance of the device.Chemical mechanical polishing(CMP)is a common and effective method for ultra-precision machining of single crystal SiC substrates.We summarize the research status of the single crystal SiC substrate in chemical mechanical polishing processing, categorize and analyze the advantages and disadvantages of various categories and limitations of the application according to the principle of processing, and points out the development prospects in the field of chemical mechanical polishing.