Zn or Mg ions doped hydroxyapatite (HA) particles were successfully developed by introducing various concentration of Zn or Mg in the starting solution using wet chemical precipitation method and followed a hydrothermal treatment. The products were identified as HA by XRD and FTIR, and the precipitated particles had a rod-like morphology. All the products for Mg and Zn ions concentration in the preparation solution less than 40 mol% were identified as HA. Substitution of Mg and Zn in HA crystal would impair the crystallization of HA and significantly reduce the length of a, c values of HA unit cell, which clearly demonstrated that Mg or Zn ions were structurally incorporated into the apatite crystals, they were not just absorbed on the surface of crystals.