Disclosed is a continuous riveter capable of firing blind rivets in succession to caulk sheet metal or the like. A seal member 71 located on the oil chamber 6 side and a seal member 72 located on the air chamber 4 side are provided in an oil cylinder 1 where an oil piston 2 separates the oil chamber 6 of the oil cylinder 1 from the air chamber 4 of an air cylinder 3, and a portion of the oil cylinder 1 which is between seal members 71 and 72 is provided with an air vent 19; and a seal member 74, 76 located on the oil chamber 16 side and a seal member 73, 77 located on the air chamber 14, 15 side are provided in a jaw case piston 20 and in a nose piston 28, the seal members 74, 76 and 73, 77 sealing an area between the oil chamber 16 and the air chamber 14, 15, and the pistons 20 and 28 between the seal members 74, 76 and 73, 77 are each provided with an air vent 75, 78.