With the widespread application of non-conducting tough materials, such as ultrawhite glass in MEMS recent years, many difficulties have arisen in the processing of these kind of material with eigen-structure characteristics. By analyzing the generation principle of interelectrode gas film of this kind of material, the breakdown characteristics of gas film under different power supply parameters were studied, and the relationship between the process parameters and the forming quality, material removal rate under the condition of gas film stability was further analyzed, so as to realize the optimal selection and successful machine of the ultrawhite glass micro array holes.