The invention relates to an antibacterial functionalized artificial joint with a silver-loaded nanotube array surface. The surface of a metal substrate of the artificial joint is provided with a silver-doped sodium titanate nanotube array layer with a tubular structure. The inside of the silver-doped sodium titanate nanotube array layer is further loaded with bone morphogenetic protein (BMP). A preparation method of the antibacterial functionalized artificial joint with the silver-loaded nanotube array surface comprises the following steps: firstly selecting pure titanium or titanium alloy to process the artificial joint; then adopting the two-step anodizing technology to obtain a titanium dioxide nanotube array layer with a tubular structure on the surface of the pure titanium or titanium alloy artificial joint; adopting the alkaline hydrothermal synthesis technology to convert the titanium dioxide nanotube array layer into the sodium titanate nanotube array layer; doping trace silver in the sodium titanate nanotube array layer by solution impregnation iron exchange; and finally adopting the centrifugal load technology to load the bone morphogenetic protein in the silver-doped sodium titanate nanotube array layer.