A dosing apparatus comprises a dosing unit (2； 2 02； 302； 402； 502), provided with casing means (5； 205； 305； 405； 505) for supporting and/or containing dosing means (50； 250； 350； 450； 550), and supporting means (40), that are associable in particular with a filling machine, for supporting and locking said dosing unit (2； 202； 302； 402； 502) in a mounting configuration (A) ； the apparatus comprises coupling means (60) associated with casing means (5； 205； 305； 405； 505) and slidingly insertable into or disconnectable from guiding means (41) of the supporting means (40) along a first direction (X), the supporting means (40) further comprising fixing means for reversibly locking the coupling means (60) to the guiding means (41) in the mounting configuration (A).
