Abstract: The present invention relates to a process for the production of a glass from silica as a raw material by a vacuum melting method, in which a high quality glass is produced efficiently by compounding a silica powder containing an excess amount of the accelerator for phase conversion and silica powders containing substantially no such accelerator or by introducing silica powders in a solution containing an accelerator for phase conversion, adding an acid or basic component to the mixture to adjust the pH thereof, stirring the mixture for mixing, and subjecting the mixture to dehydration and drying to obtain silica powders containing the accelerator for phase conversion in proper quantities, filling the resultant silica powders in a vessel and heating the powder to form a sintered molded body having cristobalite phase having a self-supporting property and also having a proper matrix strength and a high porosity, and then heating the sintered body under vacuum.