The invention belongs to the technical field of antibacterial implant materials, and discloses a copper oxide-doped potassium-sodium niobate antibacterial piezoelectric ceramic implant as well as preparation and application of the implant. The method comprises the following steps: (1) adding a solvent, niobium pentoxide, sodium carbonate and potassium carbonate into a ball milling device for ballmilling, standing, drying, calcining, and grinding into powder, to obtain potassium-sodium niobate precursor powder; (2) adding a solvent, copper oxide and the potassium-sodium niobate precursor powder into the ball milling device for ball milling, standing, drying, and calcining, to obtain copper oxide-doped potassium-sodium niobate ceramic powder; (3) evenly mixing the copper oxide-doped potassium-sodium niobate ceramic powder with a binder, granulating, forming, discharging glue, performing dense sintering, to obtain a ceramic sheet; and (4) polarizing the ceramic sheet, to obtain the copper oxide-doped potassium-sodium niobate antibacterial piezoelectric ceramic implant. The method is simple, and the prepared implant has a good antibacterial effect and stability.