One of the significant challenges in designing an ideal cage is the mechanical modulus mismatch between the implant and surrounding host tissue which results in stress shielding. In this study, a nano-hydroxyapatite/polyamide 66 (n-HA/PA66) composite with mechanical properties close to spongy bone to be designed and characterized as an intervertebral fusion cage to perform spinal fusion between vertebrae in the lumbar spine. A pure natural nanohydroxyapatite (n-HA) powder was prepared by annealing bovine bone at 1000°C followed by 10h mechanical alloying. The nano-hydroxyapaptite/ polyamide 66 and polyamide 66 (PA66) cage were prepared by injection method. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrophotometer (EDS) were used to characterize the powder and composites samples. The results showed that addition of 20% nanohydroxyapaptite results in the improvement of both mechanical and bioactivity properties. The optimum n-HA/PA66 exhibited the compressive strength and elastic modulus of 46.98 ± 2MPa and 1.53 ± 0.3GPa, respectively, which is close HAMID REZA JANGHORBAN 22 to spongy bone. In addition, observation of the superior apatite formation ability of n-HA/PA66 compared to PA66 indicates that it can be used as a bone replacement material.