Inorganic antibacterial materials consist of the antibacterial ions, the additives and the carrier. In this study, we synthesized a new inorganic antibacterial material, of which Ag+ was selected to be the antibacterial ion, lanthanum nitrate served as the additives, and the white carbon black was chosen as the carrier, which was prepared by a sol-gel method. The as-synthesized antibacterial material was characterized by inductively coupled plasma, particle size measurement instrument, and enumeration tests. The result showed that this material has loose and dispersive structure, good thermal and light stability. The possible antibacterial mechanism was also proposed through all the experimental data in this study.