Orthopedic surgery and postoperative inflammation are easy to induce oxidative stress, which hinders the process of bone repair. Bioactive ceramics have excellent osteogenic properties, but lack the ability to resist oxidative stress. Therefore, it is of great significance to develop a bioactive ceramic material with antioxidant function. Here, cobalt-incorporated chloroapatite (Co-MS-TCP) was prepared by a molten salt method, in which the mixture of lithium chloride and potassium chloride was used as a molten salt system, and β-phase tricalcium phosphate (TCP) and cobalt chloride hexahydrate (CoCl₂∙6H₂O) were used as raw material and cobalt source, respectively. The antioxidant ability of Co-MS-TCP was determined by catalyzing H₂O₂ clearance. The cytocompatibility and anti-oxidation of Co-MS-TCP were further evaluated by analyzing the changes of cell viability and intracellular reactive oxygen species (ROS). Results showed that Co-MS-TCP with controllable cobalt content can be prepared by a molten salt method with changing the addition amount of CoCl₂∙6H₂O source. The scavenging capacity of H₂O₂ increased with the increase of cobalt content in chlorapatite, and more than 90% of H₂O₂ could be scavenged within 6 h due to the catalytic activity of Co-MS-TCP. Furthermore, cell experiments confirmed the cytocompatibility and antioxidative property of Co-MS-TCP. 3% Co-MS-TCP at a concentration of 1.5 mg·mL^-1 could still ensure the survival rate of bone marrow mesenchymal stem cells and chondrocytes to be higher than 85%, and 3% Co-MS-TCP can also significantly reduce the content of intracellular ROS for the H₂O₂-stimulated cells. Therefore, molten salt method is an effective way to prepare cobalt-incorporated bioactive ceramics with antioxidative property, which also provides a promising strategy for the development of functional bioactive ceramics with high catalytic activity and biocompatibility.