Nanocrystalline Hydroxyapatite, which is similar in composition and crystal structure of natural bone, is found to be ideal bone graft substitute due to its controlled resorption in the body fluid upon implantation. This paper reports on a simple combustion technique for synthesizing nanocrystalline hydroxyapatite powder from Eggshell, Diammonium hydrogen phosphate and Citric acid. Fourier - Transform Infrared Spectroscopy and powder X-ray diffraction methods were employed to characterize the sample for phase formation. The particle size is calculated using XRD data, which shows an average diameter of 44 nm. Chemical analyses to determine the Ca:P atomic ratios in synthesized ceramics were performed and it is found to be 1.6.