The invention discloses a sustained-release antibacterial compound bone grafting material and a preparation method thereof. The sustained-release antibacterial compound bone grafting material is mainly prepared by mixing nanosilver/TMC-207 sustained release microspheres, nano-hydroxyapatite and calcium phosphate cement powder. The preparation method comprises the following steps: firstly, preparing the nanosilver/TMC-207 sustained release microspheres by an O/O emulsion-solvent evaporation method, wherein PLGA is used as a carrier material; secondly, mixing the nanosilver/TMC-207 sustained release microspheres, the nano-hydroxyapatite and the calcium phosphate cement powder, and blending an obtained mixture with deionized water to obtain paste; setting and drying the paste to obtain the slow-release antibacterial compound bone grafting material. The sustained-release antibacterial compound bone grafting material disclosed by the invention has the advantages of long local drug release time, obvious sterilizing effect and high bone repairing capability. The preparation method has the advantages of being simple and convenient to operate and lower in cost.