It is an object of the present invention to provide a method for effectively washing a used “sevoflurane storage container” without using expensive sevoflurane as a washing liquid. This object is achieved by employing the washing method, comprising the steps of: creating a state in which at least sevoflurane vapor is present in the storage container (step A)； bringing a “liquid containing water as a major component” into contact with the inner wall of the sevoflurane storage container in the state in which sevoflurane vapor is present in the storage container and draining the liquid outside of the storage container while the liquid remains liquid after step A (step B)； and introducing a drying gas into the storage container so as to drain the liquid remaining on the inner wall of the storage container together with the drying gas outside of the storage container after step B (step C).
