In the present study pure hydroxyapatite (HAp) and Magnesium (Mg) doped hydroxyapatite (HAp) powders were prepared by using chemical precipitation method. The samples were characterized by XRD, FT-IR, SEM, EDAX, UV and PL. The Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were performed to analyze the morphology and crystal structure of Pure Mg and Mg Doped Hydroxyapatite nanoparticles, respectively.The results of Fourier Transform Infrared Spectroscopy (FT-IR) provides information on the presence of functional groups present in the synthesized sample. Morphological structure and purity of the samples were analysed by scanning Electron microscopy (SEM) and Energy Dispersion X-ray Diffraction (EDAX) techniques. The optical properties were carried out by Ultra Violet spectroscopy (UV) and Photo Luminance Spectroscopy (PL). The XRD spectra confirmed that the Mg doped Hap nanoparticles have polycrystalline hexagonal structure and crystallite size in the range.