Abstract: A new type of seawater uranium extraction material PAN-h-PAMAM-A with effective antibacterial property was prepared by grafting hyperbranched poly(amido amine)(h-PAMAM) onto polyacrylonitrile(PAN) fibers by a one-step hydrothermal method and then alkali treatment. The surface functional groups and morphologies were characterized by Fourier transform infrared spectroscopy(FTIR) and scanning electron microscope(SEM). The adsorption properties of uranium under different conditions(pH, adsorption time and salt ion concentration) were studied through a series of adsorption experiments. The compe-titive ion experiment shows that the material has a good selective adsorption capacity for uranyl ions. The equilibrium adsorption capacity of PAN-h-PAMAM-A in the uranium solution reaches (296.43±4.88) mg/g (n=3, pH=8.0, ρ0=20 mg/L). The kinetic simulation shows that the adsorption conforms to the pseudo-second-order kinetic equation, and the isothermal simulation shows that the adsorption conforms to the Freundlich equation, so the adsorption is heterogeneous, multi-layer chemical adsorption process. In addition, after repeated adsorption and desorption cycles, PAN-h-PAMAM-A can still maintain excellent adsorption capacity and show very good antibacterial properties to marine bacteria, and the introduction of h-PAMAM is expected to comprehensively improve the marine applicability of materials to extraction uranium from seawater.