The invention discloses a preparation method of an IL-4R resistant single-chain antibody and application of the IL-4R resistant single-chain antibody to tumor resistance. The preparation method comprises the following steps: performing animal immunization, constructing pCANTAB5E-scFv recombinant plasmids, constructing IL-4R resistant antibody libraries, enriching and screening phage antibody libraries, optimizing scFv sequences, constructing pET-32a-scFv recombinant plasmids, performing enzyme digestion and identification on pET-32a-scFv recombinant plasmids, expressing cFv recombination protein, performing SDS-PAGE analysis, performing renaturation and purification on expression protein, performing Western blot analysis and the like. According to the invention, the stable and specific preparation method of the IL-4R single-chain antibody is established and can be used for intervening lung cancers in vivo and in vitro through purification protein, a new experiment basis is provided for treating the lung cancer, and a favorable foundation is laid for further developing of a novel antitumor drug.