The aim of this work is to improve the mechanical properties of calcium phosphate bone cement (CPC) by appending chitosan microspheres to CPC base. That chitosan degrades rapidly than bone cement has been proved by previous investigations. Porous CPC has low compressive strength because of the pores in it weakening the structure. Additive chitosan microspheres can improve the mechanical properties by bearing the compress with the CPC base and produce pores after degradation. This study investigates the effect of chitosan microspheres on the setting time, mechanical properties, phase evolution and morphology of CPC. The additive proportion of chitosan microspheres ranges from 0 wt% to 30 wt%. Compared with original CPC, the modified CPC has higher compressive strength, without significantly affecting the chemical properties. The phase composition of the CPC is tested by XRD. The microstructures of CPC are observed using SEM. The final setting times range from 5~15 minutes and can be modulated by using different liquid and powder (L/P) ratio.