The invention discloses an antibacterial active carbon fiber and a preparation method thereof, and belongs to the technical field of carbon fiber; the antibacterial active carbon fiber comprises a first antibacterial layer; the bottom of the first antibacterial layer is sequentially paved with a first pre-disinfecting layer, a second antibacterial layer, a second pre-disinfecting layer and a thirdantibacterial layer from top to bottom; agent storage cavities are horizontally crossed and distributed in the first, second, and third antibacterial layers, a first agent storage layer and a secondagent storage layer are arranged in each agent storage cavity layer, and agent outlets which are uniformly distributed are formed in the first agent storage layer. According to the invention, carbolicacid, nano zinc and nano silver are added into the activated carbon fiber, the silver and the zinc have a sterilization function, and meanwhile, the carbolic acid, ethylene glycol and a bamboo-wood vinegar antibacterial liquid can be used for double sterilization, so that the sterilization capability is enhanced.