Nanocrystal carbonated hydroxyapatite was prepared by lecithin-controlled chemical precipitation in synthetic body fluid (SBF). The reactant was aged and heated at 850 ℃ for crystallization. The morphology and microstructure of the carbonated hydroxyapatite were investigated using transmission electron microscope( TEM ), X- rey diffraction (XRD) and FTIR. The experimental results demonstrate that the shapes of earbonated hydroxyapatite particles display spheres with the average size of 20- 28 nm, and carbonated hydroxyapatite contained carbonate ions, similar to mineral of bone tissues.