The invention refers to a setting module for an illumination apparatus (2) of an optical instrument (1), in particular of a microscope, in which the illumination apparatus (2) comprises a light source (4), an illuminating optical system, and positioning elements (7, 8, 9, 16) with which the position of the light source (4) and/or of the illuminating optical system within the illumination apparatus (2) can be modified. The setting module (17) comprises a module housing (18) having at least one drive device (19, 20, 21, 22) and coupling members (27, 28, 29, 30) for the transfer of a drive motion to the positioning elements (7, 8, 9, 16). Also described is an illumination system comprising the illumination apparatus and the setting module. The result is to create an alignment capability with excellent functionality and user-friendliness, thereby making possible rapid positional adjustment of the light source and/or the illuminating optical system in the context of use under clean-room conditions.