The invention provides a dual-coiled pipe energy-saving and efficient reaction kettle capable of discharging gas by adopting a jacket, and belongs to the technical field of energy saving. The dual-coiled pipe energy-saving and efficient reaction kettle comprises a kettle body, an upper coiled pipe, a lower coiled pipe, the jacket, a stirring paddle, a baffle and the like, wherein the outlet of theupper coiled pipe is communicated with the jacket; the jacket is used as a vapour-liquid separator; the coiled pipes are circular; a traditional serial connection mode of spiral coiled pipes is changed into a parallel connection mode, so that the steam pressure drop is reduced; the upper coiled pipe is optimally matched with the lower coiled pipe in size structure; and by cooperation with the structure of the stirring paddle and the design of the baffle, materials in the kettle body flows well in the axial direction and the radial direction, and a turbulence is formed near the coiled pipes, so that the material heating uniformity is effectively improved. The integration level of the system is improved, the total cost is reduced, and the heat exchange efficiency is greatly improved. Sufficient recycling of waste steam is facilitated, the energy-saving effect is remarkable, and meanwhile, the waste steam emission is greatly reduced, and the environment-friendly effect is obvious.