The invention relates to a nozzle of a straw burner. The nozzle is composed of a high-temperature resisting nozzle head, a nozzle outer barrel and a water jacket inner barrel. The water jacket inner barrel is concentrically sleeved with the nozzle outer barrel. Cyclone flow deflectors are mounted in an annular gap between the end, close to the high-temperature resisting nozzle head, of the water jacket inner barrel and the nozzle outer barrel. According to the nozzle of the straw burner, the designed water jacket inner barrel can be used for reducing requirements for the material of the nozzleinner barrel, and the fire spray temperature of the nozzle can be made higher.