The invention discloses an environmentally-friendly flexible polyvinyl chloride cable sheath composition. The environmentally-friendly flexible polyvinyl chloride cable sheath composition is prepared from, by weight, 20-30 parts of bisphenol, 12-30 parts of stearic acid, 22-30 parts of ABS resin, 28-36 parts of polyvinyl chloride resin, 9-20 parts of ABS high-glue powder, 8.9-12.6 parts of an antioxidant 1035, 25-36 parts of maleic anhydride grafted ethylene, 5-9 parts of a vinyl acetate copolymer, 6-16 parts of mullite powder, 13-22 parts of asbestos powder, 31-39 parts of calcium carbonate, 10-15 parts of perlite, 9.3-15.2 parts of poly acid ammonium, 35-38 parts of pentaerythritol, 25-39 parts of antimony trioxide slightly crosslinked resin, 19-39 parts of a flame retardant, 10-20 parts of a flame retardant synergist, 20-26 parts of chlorinated rubber, 8.2-18.6 parts of an ultraviolet light absorber, 15-22 parts of a stabilizer, 30-35 parts of a lubricant, 42-49 parts of a calcium carbonate material and 55-59 parts of a polypropylene material. The environmentally-friendly flexible polyvinyl chloride cable sheath composition is simple in technological process and reasonable in raw material proportion, has good thermal insulation and fire proofing property, ensures the normal use of a cable, prolongs the service life of the cable, is good in use effect and guarantees the quality of a cable product.