PURPOSE: To produce hexafluoroacetone in high selectivity and one-pass yield, by reacting hexafluoropropene with O2 in the presence of a catalyst produced by supporting a noble metal selected from Ru, Rh, Pd, Pt and Ir on activated carbon.

CONSTITUTION: Hexafluoroacetone is produced by contacting hexafluoropropene and molecular oxygen with a catalyst produced by supporting about 0.3W5wt.% of noble metal selected from Ru, Rh, Pd, Pt and Ir on activated carbon. A catalyst containing 5wt.% of Pd can be produced e.g. by impregnating 1N HCl solution of PdCl2 into activated carbon, washing with water, drying at 120°C and reducing with hydrogen at 450°C. The compound is useful as a modification monomer for ethylene-tetrafluoroethylene copolymer, a raw material for vulcanizing agent for a vinylidene fluoride-hexafluoropropene fluororubber, solvent and other intermediates for chemical reaction, etc.