Metals,due to their unique and excellent antibacterial properties,have been widely used in biomedical fields. However,their antibacterial mechanisms are not yet completely clear,so that studies on metal toxicity to bacteria have been a frontier in recent years. There are two main antibacterial mechanisms that have been reported so far. One is based on oxidative damage to bacte?ria induced by the reactive oxygen species,and the other is based on structural changes induced by the Coulomb attraction. The results of bacterial damage could be due to the combination of the two mechanisms. In this paper,current research progress in antibacterial mechanisms of metal has been discussed,which will technically facilitate further development and applications of antimicrobial metal?lic materials.