To provide a catalyst for treating a silicone-containing gas of which the carrier is a heat-resistant glass fiber containing silica as a main component, preventing the catalyst activity from being deteriorated by adsorbing a silicone gas.

The catalyst for treating the silicone-containing gas is a film of chromium oxide (Cr2O3) stuck on the surface of the carrier comprising a non-porous glass fiber and a catalyst in which one or more of metals in the platinum group (Pt, Rh and Pd) deposited on the film of chromium oxide (Cr2O3). The catalyst is prepared in such a way that the surface of the carrier made of the non-porous glass fiber is coated with a mixed solution of a chromic acid water solution and a polyhydric alcohol, baked at 450-500°C to make the film of chromium oxide (Cr2O3), coated with a mixed solution of a solution containing one or more kinds of metals in the platinum group (Pt, Rh and Pd) and the polyhydric alcohol, and baked at 150-200°C. The carrier made of the non-porous glass fiber is composed of a plain fabric of fine threads blended with thick thread spacers.