Hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂, HA) fibers were prepared by electrospinning a precursor mixture of Ca(NO₃)₂·4H₂O and (C₂H₅O)₃PO with a polymer additive, followed by a thermal treatment. The X-ray diffraction (XRD) analysis of the annealed composite fibers revealed that pure HA phase could be obtained by annealing at 600°C for 1 h. The scanning electron microscopy (SEM) analysis showed the surface of as-electrospun composite fibers with an average diameter of 50 m was smooth due to the amorphous nature of the polymer. However, the surface of the calcined HA fibers was rough because of the complete removal of the polymer. The pure HA fibers obtained by electrospinning in this work were up to 10 mm in length and 1030 m in diameter and the hydroxyapatite grain size was 1 m in the HA fibers.