For the purpose of developing precision polishing method of a diamond stylus for video disc player (CED type), polishing technology using siliconoxide deposited polishing disk is discussed experimentally in this paper. Stock removal rate of the diamond stylus, using the silicon-oxide deposited polishing disk, is in proportion to the polishing distance and load. This fact is as same as the conventional polishing technology. However, the stock removal rate is found to be influenced by the relative humidity of the polishing environment. When polishing in 20 RH%, the stock removal rate is four and a half times larger than that in 60 RH%. In order to obtain a siliconoxide polishing disk which can achieve larger stock removal rate, deposition experiment and the siliconoxide analysis is carried out. Thereby, a siliconoxide which is deposited with SiO in O₂ plasma gives the largest stock removal rate. This is due to the fact that the siliconoxide best for the polishing has the most Si-O bonds and less H₂O, Si-OH.