Hydroxyapatite whisker was the reinforcement phase to prepare whisker/calcium phosphate cement composites, which was obtained by homogeneous precipitation method, with 2.5~15 microns in length, 2~30 length/diameter ratio. Mechanical properties and microstructure of composites were tested. With the increase of hydroxyapatite whisker addition, composites strength reduces after the first rise. When hydroxyapatite whisker is added to 4%(wt), the composite achieves the maximum strength. SEM method was used to observe fracture microstructures of composite materials. As a result, dispersion degree of the HA whisker affects the strength of the material. Too much whiskers can form agglomerates, which weaken composite strength.