Quartz glass is one of the key optical components in the precision optical systems such as UV lithography and laser nuclear technology. The chemical polishing method is proposed to solve the defect issues of the surface or sub-surface damages and etch pits which easily occur in the quartz glass during the machining process. The chemical polishing principle and the working process of quartz glass slices are introduced in this paper. The orthogonal experiment method is used to optimize the chemical polishing process parameters for the quartz glass slices, and the effects of main ingredients of chemical polishing fluid, temperature of polishing fluid and polishing time on the surface roughness are analyzed. The results show that the surface average roughness and the highest transmittanceof quartz glass slices, polished by the mixed solution of NH4HF2 and additive glycerol, can reach about 100 nm and 89%, respectively.