Seal device for a vehicle door, in particular of commercial vehicles

The sealing device comprises a door portal, which is formed opposite to the front side of the door. The front side of the door or the door portal is provided with a mold piece or sealing portion (20) in the area of the lower door front side, whose outer contour or thickness varies in the longitudinal direction of the front side of the door. A mold closure is provided, which is formed between the sealing portion fixed at the door front side and the door portal during the door closing position.