Hydroxyapatite (HA) is one of the most attractive biomaterials and widely used as a bone substitute due to its compositions are similar to the minerals in teeth and bones. Understanding of natural HA properties are useful in order to produces high quality of HA. In this paper, we report an easy and low cost method to extract the natural HA from femur cow bone and subsequently sintered at different temperature from 900 oC to 1300 oC. Structural, composition and surface morphology of natural Hydroxyapatite (HA) at different sintering temperatures (900 ̊ C, 1000 ̊ C, 1100 ̊ C, 1200°C and 1300 ̊ C) were discussed. The HA structural, composition and surface morphology were studied by using X-Ray Diffractometer (XRD), Fourier Transform Infrared (FTIR) and Scanning Electron Microscope (SEM), respectively. The results show the main HA phases were detected in the range of 31.72o - 31.82o (2Ө) for all sintered HA corresponding to 211 plane. The crystallite size of HA increases with sintering temperature from 900 ̊C to 1100 ̊C. Spectrums of FTIR revealed the existences of functional groups of carbonate (CO3 2-), phosphate (PO4 3-) and hydroxyl (OH-) peaks. SEM micrographs presented small and homogenous grains from 900°C to 1100°C. The grains look interconnected as sintering temperature increased at 1200°C and 1300°C. From this study, sintering process was found to be an easy and low cost method to produce natural HA from femur cow bones.