Abstract: Decomposition of hydroflurocarbon HFC-134a is tested catalytically and chemically in thisstudy.Experimental results are as follows,HFC-134a is stable,not decomposed,without using cata-lyst even if rising reaction temperature up to 500℃,but decomposed to CO and CO2 in the atmosphereof air and water vapour with using catalyst.CFC-12 is decomposed more easily than HFC-134a,and its reaction products don’t contain CO.The deactivation of catalyst arises obviously from reactionproduct of HF. The superoxide ion(O2￣-)is possessed of a strong ability to decompose HFC-134ainliquid phase. The HFC-134a in high concentration is decomposed almost completely at the ambienttemperature.