GB/T 1031-1995 specifies the parameters and values of surface roughness. It specifies the evaluation parameters of surface roughness, such as contour arithmetic average deviation Ra, micro-unevenness ten point height Rz, etc., and explains in detail the meaning of each parameter and the surface characteristics characterized. The numerical series corresponding to different parameters are given, covering various degrees of value from roughness to fineness. These parameters and values provide the basis for the quantification of product surface mass, which is convenient for the mechanical manufacturing, precision machining and other industries to accurately set surface roughness standards according to different needs, and help improve product performance and mass.