The invention discloses a catalyst for low-temperature catalytic combustion of chlorine-containing organic matters. A transition metal oxide modified with sulfuric acid is used as a catalyst; the transition metal oxide is zirconium oxide, titanium oxide or ferric oxide; the sulfuric acid exists in the surface of the transition metal oxide in the form of bidentate sulfate; the mass fraction of sulfur element is 0.5-3wt%. The invention also discloses a preparation method for the catalyst and an application thereof in the low-temperature catalytic combustion of the chlorine-containing organic matters. The catalyst made from the transition metal oxide modified with sulfuric acid according to the invention has higher catalytic activity and can catalyze the combustion oxidation of the chlorine-containing organic matters, including chlorine-containing aliphatic hydrocarbon and chlorine-containing arene, under lower temperature; the main combustion products include carbon dioxide, hydrogen chloride and chlorine; no chlorinated product with secondary pollution is formed; the preparation is simple; the cost is low and the service life is long; the catalyst is suitable for treatment of complex industrial waste gas; the catalyst has an application prospect for industrial waste gas treatment.