A hinge for doors or for wings of furniture items comprises fastening elements (1, 2) provided with fixed pivot pins (7', 7") and with sliding guides (9', 9"), which can be housed respectively in the thickness of the door (3) and in a corresponding fixed door post (4); arms (5', 5") for connecting the door (3) to the door post (4) connected to the fastening elements (1,2) with their first extremity (6', 6") hinged on the fixed pivot pin (7', 7") of one of the fastening elements (1,2) and with a second extremity (8', 8") engaged in the sliding guide (9", 9') of the other fastening element (2;1); and a joint (10) interposed at the extremities (6', 8', 6", 8") of the arms (5', 5") which pivotingly connects the arms (5', 5") to each other allowing their relative angular mobility. The fastening elements (1, 2) comprise connecting bodies (15', 15") movable relative to each other at least along one direction defined by at least one of three cartesian axes, respective adjusting means (16, 17, 18) being provided thereto. The arms (5', 5") have mutually different lengths at least in correspondence with their first portion (11', 11"), positioned between the respective first extremities (6', 6") and the intermediate joint (10), to allow the opening of the door (3) with the rotation thereof relative to the door post (4), to a condition of parallelism between door (3) and door post (4) and without substantial interposition of space.