A concealed door hinge for pivotably mounting a door leaf on a door frame, comprising: - two hinge bodies (2, 3), - a joint, via which the two hinge bodies (2, 3) are connected to one another, - wherein one of the hinge bodies (2, 3) is insertable into the narrow side of the door leaf and the other hinge body (3, 2) is insertable into the door frame, - front fastening plates (5, 6) and rear fastening plates (7, 8) which are installable on respective attachments (21, 31) on ends of the hinge bodies (2, 3) which are spaced apart from one another in the longitudinal extension and using which the hinge bodies (2, 3) are fastenable on the door leaf and the door frame, - wherein a first adjustment device, using which the hinge body (2, 3) is adjustable separately from one another in a vertical direction (z) and a horizontal direction (y) in a plane spanned by the front face of the front fastening plates (21, 31), is arranged in each case on one of the hinge bodies (2, 3) between the front fastening plates (5, 6) and the respective attachment (21, 31), characterized in that - the adjustment device has, for the adjustment in a horizontal direction (y), a first intermediate plate and a holding plate arranged so it is displaceable in relation to the attachment in the horizontal direction (y), wherein the front fastening plate (5, 6) is connected to the holding plate using first clamping screws, which extend through horizontally aligned oblong holes in the first intermediate plate, and - the adjustment device, for the adjustment in a vertical direction (z), has second clamping screws, wherein the first intermediate plate is connected to the rear fastening plate (7, 8) using second clamping screws extending through vertically aligned oblong holes in the attachment. - two hinge bodies (2, 3), - a joint, via which the two hinge bodies (2, 3) are connected to one another, - wherein one of the hinge bodies (2, 3) is insertable into the narrow side of the door leaf and the other hinge body (3, 2) is insertable into the door frame, - front fastening plates (5, 6) and rear fastening plates (7, 8) which are installable on respective attachments (21, 31) on ends of the hinge bodies (2, 3) which are spaced apart from one another in the longitudinal extension and using which the hinge bodies (2, 3) are fastenable on the door leaf and the door frame, - wherein a first adjustment device, using which the hinge body (2, 3) is adjustable separately from one another in a vertical direction (z) and a horizontal direction (y) in a plane spanned by the front face of the front fastening plates (21, 31), is arranged in each case on one of the hinge bodies (2, 3) between the front fastening plates (5, 6) and the respective attachment (21, 31), - the adjustment device has, for the adjustment in a horizontal direction (y), a first intermediate plate and a holding plate arranged so it is displaceable in relation to the attachment in the horizontal direction (y), wherein the front fastening plate (5, 6) is connected to the holding plate using first clamping screws, which extend through horizontally aligned oblong holes in the first intermediate plate, and - the adjustment device, for the adjustment in a vertical direction (z), has second clamping screws, wherein the first intermediate plate is connected to the rear fastening plate (7, 8) using second clamping screws extending through vertically aligned oblong holes in the attachment.