Abstract: The invention relates to a fluid supply assembly for a device, particularly a printing machine. The inventive assembly comprises a lower base and is of the type in which the fluid is conditioned in an upper container which is intended to be connected to a fill opening in the base by means of a coupling. In order to mount the coupling on the base, the coupling is moved linearly along a vertical assembly axis and then pivoted around the assembly axis. The coupling comprises at least one keying pin which is received in a complementary groove in one face of the base when the coupling is being moved linearly. The invention also relates to a printing machine containing one such assembly.