In order to improve the efficiency of chemical preparation of YBa2Cu3O7?δ (YBCO) with long taps, the pyrolysis of traditional process preparing precursor film needs to be reduced to one step, so the crystallization process should be directly connected to the former without the cooling of pyrolysis. Replacing copper trifluoroacetate with copper isooctanate can alleviate the centralized heat release and the contraction of the precursor film during pyrolysis. A suitable amount of boric acid was added into the precursor solution with total cation concentration of 1.0 mol/L, after a continuous heat treatment YBCO superconducting film was obtained. Utilizing the flow state of boric acid at 200-500 ℃, boron oxide was doped into YBCO film which shows denser and smoother by filling some pores, compared with that one prepared by undoped precursor solution under the same conditions, the former shows higher superconductivity.