Abstract: The second generation semiconductor material, gallium arsenide (GaAs), is widely used in the field of microelectronics and optoelectronic devices. It is used as the basic material for substrate epitaxial growth and device preparation. The surface integrity of GaAs wafer is required to have ultra-smooth surface and no surface/subsurface damage or residual stress. The surface flattening quality of GaAs wafer determines the subsequent epitaxial layer and ultimately affects the performance of related devices. By summarizing and analyzing the intrinsic characteristics of GaAs single crystal materials and the research progress of cutting, edge grinding, surface grinding and polishing technology, the future research direction of super smooth flattening processing technology of GaAs is prospected.