Abstract: The duplex treatment consisting of plasma surface alloyed with copper followed by thermal diffusion under the bombardment of glow was carried out on Ti-6Al-4V. The antibacterial properties against Gram-negative E.coli ATCC10536 and Gram-positive S.aureus ATCC25923 of the untreated and duplex-treated stainless steel were investigated by using a spread plate method. Meanwhile, the wearing resistance is also tested. The X-Ray Diffraction(XRD)、scanning electron microscope(SEM) and Energy Dispersive Spectrometer(EDS) are exploited in order to observe and analyze the phase structure and the elementary composition of the coats,and the optical microscopy with 3D function is used to detect the wear depth. The results show that the copper concentration on alloyed surface is about 11wt% and the thickness of alloyed layer is about12μm. And alloyed surface exhibits excellent antibacterial properties against both E.coli and S.aureus . And the wearing resistance is improved significantly.