A module type flue gas heat exchanger with fluorine plastic pipes comprises a heat exchanger casing and a heat exchange pipe, wherein the upper end of the heat exchanger casing is provided with water inlets and water outlets, and the lower end of the heat exchanger casing is provided with a drain outlet. A water inlet end plate is detachably connected to the position of the water inlets and provided with water inlet holes, and a water outlet end plate is detachably connected to the position of the water outlets and provided with water outlet holes. The heat exchange pipes are U-shaped fluorine plastic heat exchange pipe bundles, water inlet ends of the fluorine plastic pipes in the fluorine plastic heat exchange pipe bundles are communicated with the water inlet holes, water outlet ends of the fluorine plastic pipes in the fluorine plastic heat exchange pipe bundles are communicated with the water outlet holes, and positioning nets are parallelly distributed in the heat exchanger casing from top to bottom at intervals. Module type design is adopted by the flue gas heat exchanger, equipment utilizing rate of the flue gas heat exchanger is greatly improved, the positioning nets are used by the flue gas heat exchanger at a fixed interval so as to fix the fluorine plastic pipes in the fluorine plastic heat exchange pipe bundles, and shaking deformation of the flexible fluorine plastic pipes caused by flowing impact of flue gas can be avoided.