we hydrothermal synthesized a β-TCP/CaS composites at various ratios using bovine trabecular bone and CaS(CaSO4.2H2O)powder,and the performance of the composites degradation and osteogenesis,were evaluated in vitro and by implantation in bone defects in rabbit femurs.These results showed that the β-TCP/CaS composites overcomed the drawback of β-TCP(degrading too slow)and CaS(degrading too fast),and that the degradation rates of the composites increasing in vitro and in vivo with increasing CaS.The results also showed that combining CaS with TCP led to enhanced osteogenic activities,most likely due to a better match between the rates of degradation and new bone formation.