The invention discloses a gas phase in-situ oxidation preparation method of an Mn-Ce-Fe-Co quaternary catalytic function PPS filter. The preparation method is that a dust collector PPS filter is usedas a carrier; PPS is subjected to surface viscosity modification processing by adopting a binding agent; after impregnation absorption and secondary low-temperature drying dehydration, the processed PPS is in contact with ozone with concentration of 10 mg/L to 240 mg/L to carry out gas phase oxidation; active metal ions are directly subjected to in-situ oxidation on the surfaces of PPS filter fibers to be converted into a form of an oxide with high active catalytic activity so as to complete preparation of the Mn-Ce-Fe-Co quaternary catalytic function PPS filter. The preparation method disclosed by the invention uses gas phase oxidation as the core innovation point, and is wide in material source, simple and stable for gas storage, simple for safety leakage check and high in production safety.