Biocompatible composite particles composed of hydroxyapatite (Ca10(PO4)6(OH)2, HAp) and ferrite (maghemite (?-Fe2O3) or magnetite (Fe3O4)) were synthesized by two-step synthesis. In this work, co-precipitation method using aqueous solution of FeSO4 and FeCl3 was employed to synthesize ?-Fe2O3 and Fe3O4 particles. It was found that the resultant phase was changed by the molar ratio of FeSO4 and FeCl3, and optimal molar ratio to suppress the coexistence of a-FeOOH was FeSO4/FeCl3=2. The suspension composed of crushed ferrite particles, Ca(NO3)2 and H3PO4 aqueous solution with surfactant ultrasonically nebulized into mist and the mist was pyrolyzed to synthesize HAp-ferrite composite particles. The shape of the synthesized composite particle was round with dimple, and the particle size was around 0.5-3?m in diameter. The composite particle showed saturation magnetization of 0.833 emu/g. Net saturation magnetization of the ferrite component was calculated to be 46.4 or 48.0 emu/g under the assumption that the ferrite was composed of ?-Fe2O3 or Fe3O4, respectively. The synthesized HAp-ferrite composite particle would be used as drug delivery system and hyperthermia etc.