To provide a cleaning method capable of obtaining a storage container of a precision substrate, such as a photomask blank, which includes an antistatic function after cleaning, and to provide a manufacturing method of the storage container of the precision substrate which achieves the antistatic function.

A cleaning method of a storage container of a precision substrate is a method for cleaning the container which stores the precision substrate. In the cleaning method, a surface active agent is used to form a coat composed of the surface active agent on a surface of the storage container during cleaning of the storage container and cleaning is performed so that the coat is left after the cleaning.