A vending machine for preparing beverages (1) comprising a product withdrawal compartment (5) of the dispensed products provided with a door (7) movable between a closed position and an open position; and a mechanical informative display (8), which is designed to reproduce a graphic sign (9) visible by a user located in front of the product vending machine (1) and comprises the door (7) and a display panel (10) arranged relatively to the door (7) in such a way that the latter gradually overlaps it during the movement from the closed position to the open position; the door (7) and the display panel (10) are also provided with respective graphic patterns (11A, 11B), and the display panel (10) is at least partially optically transparent to allow the graphic pattern (11A) of the door (7) to be at least partially visible through the display panel (10) so as to at least partially combine with or graphically interfere with the graphic pattern (11B) of the display panel (10) when the door (7) overlaps the display panel (10).