The invention discloses titanium dioxide based graphene/La<3+> carbon fibers. The titanium dioxide based graphene/La<3+> carbon fibers are prepared from a graphene/polyacrylonitrile/DMF mixed solution and a lanthanum nitrate, glacial acetic acid and tetra-n-butyl titanate mixed solution through blending and spinning, wherein the concentration of the graphene/polyacrylonitrile/DMF mixed solution is 0.0007-0.0049 g/mL, and the concentration of polyacrylonitrile is 0.08 g/mL; the concentration of lanthanum nitrate is 0.0069 g/mL, the volume ratio of glacial acetic acid to tetra-n-butyl titanate is 4:5, and the volume ratio of the graphene/polyacrylonitrile/DMF mixed solution to the lanthanum nitrate, glacial acetic acid and tetra-n-butyl titanate mixed solution is 50:9. The invention further discloses antibacterial yarn and antibacterial fabric prepared from the fibers. The titanium dioxide based graphene/La<3+> carbon fibers have the advantages that the strength is high, production equipment is simple, the operation is simple and the antibacterial effect is good.