This paper describes the influence of electrolyzed reducing water of dilute NaCl (NaCl ER water) on the surface of optical glass. First, the etching characteristic of NaCl ER water on the surface of optical glass was made clear by the comparative immersion experiments with NaCl ER water and NaOH solution. The results show that as for the etching effects on optical glass, NaCl ER water is same as the NaOH solution and becomes weak. Next, the influence of NaCl ER water on the surface shape, chemical composition and chemical bonding of the surface of optical glass was made clear, by the observation using the AFM image and the result of ESCA (Electron Spectroscopy for Chemical Analysis). The results indicated that NaCl ER water did not have any bad influence on the surface shape, chemical composition and chemical bonding of optical glass. Lastly, by the washing experiment, the efficiency of NaCl ER water in abrasives particulate removal is verified.