The invention relates to a method for increasing decomposing velocity of Freon in the processes of burning and hydrolyzation of the Freon, pertaining to the technical field of poisonous and harmful waste-gas purifying. Fuse salt is adopted as a heat carrier and crystals that have the granularity of 50 micron to 300 micron, such as KNO3, NaNO3, AlCl3, Ca(NO3) 2 and KCl are selected as heat carriers of the fuse salt and are put into a reactor according to proportion by weight after being evenly mixed, the reactor is heated to 350 DEG C to 500 DEG C so as to ensure that the fuse salt is completely in the melting state. The Freon, vapor and oxygen are pumped to the reactor and the Freon quickly decomposes in the existence of the vapor and at the comparatively low temperature. The decomposing rate of the Freon is more than 98 percent and by adopting the method, the temperature and the time required by the Freon decomposition as well as the energy consumption are reduced.