The invention discloses a TiO2/AgNPs/PSf composite forward osmosis membrane, a preparation method thereof, and an application of the TiO2/AgNPs/PSf composite forward osmosis membrane in removal of tetracycline drug resistance genes by a forward osmosis membrane water treatment technology. The composite forward osmosis membrane sequentially comprises a polyethylene terephthalate (PET) non-woven fabric supporting layer, an electrostatic spinning base membrane layer and a polyamide active layer. The preparation method comprises the following steps: synthesizing antibacterial TiO2/AgNPs compositenanoparticles; uniformly dispersing the TiO2/AgNPs composite nanoparticles in a mixed solvent of dimethyl formamide (DMF) and N-methylpyrrolidone (NMP), and adding polysulfone (PSf) to prepare a spinning solution; standing and defoaming the spinning solution, and then carrying out electrostatic spinning on the spinning solution on a PET non-woven fabric to prepare a nanofiber base membrane; and carrying out an interfacial polymerization reaction on the prepared nanofiber base membrane to form the polyamide active layer so as to prepare the composite forward osmosis membrane. The forward osmosis membrane prepared by the method has the characteristics of high hydrophilicity, high water flux and high antibacterial efficiency, and has good interception performance on various tetracycline resistance genes.