Apatite nuclei were synthesized by raising pH of simulated body fluid (SBF). Poly (lactic acid) (PLA) microspheres were soaked in apatite nuclei suspension, and then apatite nuclei were attached to surfaces of the PLA microspheres. When these PLA microspheres were soaked in SBF, apatite nuclei on the PLA microspheres induced HAp. As a result, PLA microspheres coated with HAp were fabricated. The HAp-coated PLA microspheres were soaked in acetone. The PLA core was dissolved out, and then consequently hollow microcapsules constructed of HAp were fabricated. As HAp microcapsules have properties of bioaffinity and non-toxicity, they were expected to be applicable to an excellent carrier of drug delivery system.