The hinge for mounting a door or a piece of furniture provided with a front frame comprises a base plate fixable to the front frame of the piece of furniture, an intermediate plate slidably connected to the base plate and movable by an adjusting cam, a hinge arm connected to the intermediate plate swingably according to a transversal axis and mobile by means of an adjusting screw; the intermediate plate, at a rear end thereof, exhibits side wings having hinging projections which project on opposite sides according to the transversal axis so as to engage rotatably in rear side holes of the hinge arm. The base plate exhibits retaining side parts for the intermediate plate, conformed and arranged such as to retain the side edges of the intermediate plate in a perpendicular direction to the longitudinal extension plane of the base plate.