The main purpose of this study was to prepare hydroxyapatite nanoparticles as pharmaceutical excipients. The first, chemical precipitation, sol-gel technique and reverse microemulsion were used to synthesis hydroxyapatite nanoparticles,then characterization of the solid was performed by IR.XRD and SEM.We can see that successful preparation out hydroxyapatite.And than, the influence of light,temperature and humidity on stability was studied. Results show that nsHAp still stability.The second,Nano-hydroxyapatite by PH value, liquidity, and many other study cited moist established the quality standards for nsHAp was established though the investigation of PH value,liquidity and hygroscopicity.,to evaluate the biological security properties of nsHAp,the nsHAp subjected to acute toxicity test,compared with control groups.The advantages and disadvantages of three methods to prepare nsHAp were were evaluated.