The present invention belongs to the field of preparation of high performance polymers, and specifically relates to a low dielectric constant polymer containing dinaphthyl and hexafluorocyclobutyl ether units, and preparation method and use thereof. The polymer is prepared as follows: under the effect of an alkali, 1-naphthol bromotetrafluoroethane ether is prepared from 1-naphthol and tetrafluorodibromoethane in an organic solvent, and then reduced by a zinc powder so as to obtain 1-naphthol trifluorovinyl ether. 1-naphthol trifluorovinyl ether is treated at a high temperature to obtain a bisnaphthol hexafluorocyclobutyl ether monomer. The monomer is subjected to oxidative coupling in the presence of ferric trichloride so as to obtain a thermal polymer containing dinaphthyl and hexafluorocyclobutyl structural units with a good film-forming property, and in a nitrogen atmosphere, the temperature for 5% weight loss (Td5%) of the obtained film is 437° C., and the carbon residue yield at 1000° C. is 54.24%. The dielectric constant (30 MHz) of the film is 2.33. The polymer is suitable for use in the electronic and electrical industries as an insulation coating layer and an encapsulating material for electron components.