The work aims to explore the antibacterial performance of TiCu alloy with rough surface after SAL. The TiCu alloy was treated by sandblasting and acid etching (SLA) in order to acquire a rough surface and then compared with SLA-Ti for study. S. aureus was used as the experimental strains to calculate the sterilizing rate through the plate colony-counting method. Dead/live bacteria staining test was carried out to observe the bacteria adhesion distribution and formation of biofilm on the surface and the change of bacteria microstructure under TEM, in order to explore the antibacterial properties of SLA-TiCu and the effects on bacterial microstructure. The surface of SLA-TiCu had the micro-submicron dual-hole scale structure and excellent antibacterial properties, with an antibacterial ratio of 100% for surface adhesion bacteria. The staining result reflected that a large number of bacteria on the surface of SLA-TiCu were dead, and no biofilm was formed, but biofilm was observed on the surface of SLA-Ti. Observed under TEM, the bacteria on SLA-TiCu were found to have obvious cell membrane dissolution phenomenon and transparent and semitransparent areas appeared inside the damaged bacteria body. Cell walls and cell membranes were damaged, cytoplasm in cells flew out, and particles and precipitates with high electron density could be seen around the damaged bacteria. The TiCu alloy treated by SLA has excellent antibacterial properties, which can effectively play the antibacterial role of Cu ions and then effectively kill the bacteria adhering to the surface, thus inhibiting the formation of biofilms on the surface. Therefore, SLA-TiCu with outstanding antibacterial performance has great potential for application in dental implants.