The invention discloses a preparation method of a high-performance fluoride rubber / silicone rubber cable sheath material. The preparation method comprises the following steps of performing primary mixing on fluoride rubber, silicone rubber, epoxy acrylate elastomer, hydrogenated butadiene-acrylonitrile rubber, maleic anhydride grafted polyethylene and methyl vinyl silicone rubber grafted methacrylic acid-2,2,2-trifluoroethyl to obtain a primary rubber compound; adding carbon nanotubes, stearic acid modified diatomite, calcium silicate, polyaniline nanofibers, sepiolite fibers and calcium hydroxide, and mixing for 1 to 5 minutes; adding 2,6-di-tert-butyl paraaminophenol, 2,5-di-tert-butylhydroquinone, nitrosodiphenylamine, butylmercaptooxo stannane, 5,5'- dimethyl-5,10-dihydracridine, and mixing for 3 to 8 minutes; adding stearic acid, inositol hexaphosphate, epoxidized linseed oil, active magnesium oxide, bisphenol AF, benzyl triphenyl phosphorus chloride, N,N'-meta phenylene bismaleimide, phenolic resin and an accelerator, mixing for 5 to 10 minutes and then vulcanizing for two times.