Antineoplastic target fusion protein with release switch and use thereof

The invention discloses fusion protein and an encoding gene and application thereof. The fusion protein consists of three parts which are a targeting carrier, a drug release switch and a warhead; one end of the drug release switch is connected with the targeting carrier, the other end is connected with the warhead; the targeting carrier is polypeptide containing the first-sixty fifth amino acid residues of sequence 2 in a sequence table; the warhead is polypeptide containing the sixty eighth-ninety third amino acid residues of the sequence 2 in the sequence table; and drug the release switch is polypeptide which can be specifically cut by serine protease (for example, urokinase, fibrinolysin and thrombin) or metalloprotein. The recombinant targeted drug protein is characterized by high identification specificity, smaller molecular weight, no immunogenicity, no anaphylactic reaction, nontoxicity and good permeability, and can carry targeted warhead to surfaces of tumor cells to kill the tumor cells, and has no