The invention discloses a high-molecular base layer special for an underfloor heating floor and a preparation method thereof. The high-molecular base layer special for the underfloor heating floor isa silica fiber board. The silica fiber board is a sandwich structure. A core layer of the sandwich structure is made of slurry A, and a surface layer is made of slurry B. The slurry B contains an N-TiO2/silica silver-loaded composite material. The high-molecular base layer is capable of, through using a floor heating system, solving problems that construction of a traditional underfloor heater iscomplicated, heat supply is separated from the floor, cost is high, efficiency is low and a construction period is long. An advanced surface layer processing technology is used, and heat supply fibersare organically fused in an interlayer of the floor and the like, so multiple textures are realized, and the different design requirements of people are satisfied.