The invention relates to a method for cleaning dissolution vessels and for the subsequent dosing of a dissolution media, and to mobile modular cleaning and dosing equipment for the implementation of said method. According to said method, injected water steam is used for the cleaning and is subsequently aspirated, together with the residues of the dissolution, and the vessel is then refilled with the desired quantity of a new dissolution media. The mobile modular cleaning and dosing equipment allows the cleaning and dosing to be carried out in situ without having to remove the dissolution vessels from the equipment or site where the dissolution tests are carried out, using self-sufficient modular equipment, and a novel steam supply line is used for the cleaning, which sprays the steam against the bottom of the vessel and the inner side walls.