A new biomimetic precipitation technique was developed to synthesize hydroxyapatite/collagen nanocomposites. The componential and morphological properties of nano-composites were investigated. It was revealed that the inorganic phase in the nano-composite was carbonate-substituted hydroxyapatite with low crystallinity. Indeed both characteristic peaks for HA and Col molecule and shifts of the characteristic peaks have indicated on HA-Col bonding. Morphology studies showed that hydroxyapatite particles with the average size of 50 nm were distributed homogeneously in the polymer matrix. According to the TEM micrographs, inorganic particles were needle-like and had regular crystallographic orientation. These results suggest that the hydroxyapatite/collagen nano-composites are promising biomaterials for bone tissue engineering.