To provide a pressurizing hood seal device which can obtain enough pressure loss without needing a seal piece and is capable of blowing in of gas, in a downward suction type sintering machine.

The shape of the end in width direction of the bottom of the skirt part 4 of the pressurizing hood 3 provided on the sintering pallet 1 of a downward suction system on sintering machine is made in labyrinth structure, and a plate 13 is installed on the sintering pallet 1 in the positions opposed to each other between the labyrinth parts of this labyrinth structure, thus it is made into alternate labyrinth structure. A part of the bottom of a comb- shaped labyrinth structure is made a magnet, and it is filled with magnetic substance.