The invention discloses a fluid type igniter for a gas blaster, and a fracturing device. The igniter comprises a casing and a filling cavity located in the casing; the casing comprises a first sub-joint, a second sub-joint and a coupling head; the filling cavity comprises a reducing agent filling cavity and an oxidizing agent filling cavity; the reducing agent filling cavity is formed in the first sub-joint, and the oxidizing agent filling cavity is formed in the second sub-joint; two ends of the coupling head are in threaded and sealed connection with one end of the first sub-joint and one end of the second sub-joint or are seamlessly welded at one end of the first sub-joint and one end of the second sub-joint; the other end of the first sub-joint is connected with a liquid filling nozzle, and the other end of the second sub-joint is connected with an inflation mechanism; an isolation thermoplastic piece is mounted in the middle of the coupling head; and an electric heating wire is packaged in the isolation thermoplastic piece and is led out of the casing through a wire. The igniter has the advantages that the manufacturing cost is low, the reaction material mixing uniformity is high, the heat releasing efficiency is high and the transportation safety is good.