A device and method for adjusting mounting of a microscope stage (14), to which an objective (38) is mounted, to a microscope stand (12), including at least one first connecting element (56) arranged on the microscope stand (12), at least one second connecting element (62) arranged on the microscope stage (14) for mounting the microscope stage (14) to the microscope stand (12), at least one first mating part (76) arranged on the microscope stand (12), at least one positioning base (66) supporting a second mating part (74), wherein the positioning base (66) adjusts the platform (16) on the microscope stand (12) and is mounted movably in a plane of adjustment that is parallel to the platform (16) with the mating parts (74, 76) being engaged, and at least one locking device (80) for locking the positioning base (66) to the platform (16).