The aim of this study was to prepare and characterize the poly (?-caprolactone)/Mg-doped fluorapatite nanoparticles (PCL/nMg-FA) nanocomposite electrospun scaffolds. The first step Of this work, The nanostructured fluorapatite (FA; Ca 10 (PO 4 ) 6 (OH) 2-x F x ) was synthesized with the starting materials of CaCO 3 , P 2 O 5 and CaF 2 via a mechanochemical process. The effects of milling time and fluorine ion concentration were investigated. The products characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR) analysis. The FA nanoparticles with an average diameter of about 15-30 nm were successfully prepared after 10 h milling time. The results show incorporation of F ions into the apatite resulted in the decrease of the lattice parameters (about 1.15 %). The effect of solvent type on distribution of nanoparticles and mechanical properties of the scaffolds was also investigated in order to obtain an optimized composition. The optimized conditions were obtained by changing the electrospinning parameters such as: Polymer concentration, applied voltage and nozzle to collector distance. Electrospun nanofibers prepared by ethanol/chloroform system are more uniform (0.692±0.0783) µm) and several times smaller than those obtained by other systems. Addition of Mg-FA nanoparticles decreased the average fiber diameters from 0.490±0.073 µm (pure PCL scaffold) to 0.322±0.199 µm (PCL-20 wt. % nMg-FA scaffold). Optimized nanofibrous scaffold was obtained by 5 wt. % nMg-FA while its tensile strength and elastic modules were significantly enhanced compered to PCL scaffolds. The scaffolds were characterized with regard to structural and mechanical properties, degradation, bioactivity and cellular interactive responses. However, due to the high surface energy of such , they cannot be well dispersed in a biopolymer matrix to prepare a polymer/ceramic composite, which is usually demanded for tissue engineering applications. To overcome this shortcoming, the surface of nMg-FA was modified using a few well-known natural amino acids as the cost-effective and environment-friendly biomaterials in the present research. The L-leucine, L-isoleucine, L-alanine and L-phenylalanine amino acids were employed as the coupling agents and the surface modification of nMg-FA was carried out by means of sonication technique. The results confirmed that using amino acid molecules leads to the uniform dispersion of nMg-FA in the organic environment by making the surface of hydrophobic, although the length and chemical reactivity of amino acid molecules affect the efficiency of dispersion. The uniform distribution of nMg-FA is a desired condition for polymer/ceramic composite preparation which is highly applicable for biomedical purposes. At that point, Mg-doped fluorapatite nanoparticles was surface modified using amino acids as modifier and PCL surface modified Mg-doped fluorapatite nanoparticles scaffolds were developed. This scaffold was also characterized with regard to structural and mechanical properties, degradation, bioactivity and cellular interactive responses. Keywords : Mechanochemical process, Electrospining, Mg-doped fluorapatite nanoparticles, Nanocomposite, Surface modification.