The present invention provides a method for the decomposition of chlorofluorocarbons to hydrofluoric acid, hydrochloric acid and carbon dioxide by the chlorofluorocarbons' reaction with water at a temperature of 200 .degree. C. or higher and in the presence of a catalyst material consisting of a metal selected from the group consisting of Ti, Zr, Nb and an alloy consisting of at least two elements selected from the same group. The catalyst material may also be composed of an alloy consisting of up to 80 atomic % of at least one element selected from the group consisting of Ni and Co and the substantial balance of being at least one element selected from the group consisting of Ti, Zr and Nb. The metallic catalyst materials of the present invention have a very high catalytic activity for the decomposition of flons at relatively low temperatures and can retain their high activity during the decomposition process, even if they are converted into fluorides.