Method for preparing quartz glass crucible

A method for preparing a quartz glass crucible which involves a substrate forming process of feeding a silicon dioxide powder to the inside of a rotating mold to form the powder by centrifugal force into a formed product having a shape of a crucible and then melting the formed product by heating to prepare a semi-transparent quartz glass crucible substrate, and an inner layer forming process of feeding again a silicon dioxide powder into a hot atmosphere inside the crucible substrate during or after forming the crucible substrate to form an inside layer of transparent quartz glass on the inside surface of the crucible substrate, characterized in that it further comprises introducing water vapor to the inside of the crucible substrate in at least a part of the period of the inner layer forming process. A quartz glass crucible prepared by the method allows the pulling up of a silicon single crystal which is free from the occurrence of vibration of a silicon melt surface or of dislocation of a crystal caused by the exfoliation of a piece of quartz glass and thus exhibits a high yield.