Hydroxyapatite (HA) has been used clinically for the last 30 years in medicine and dentistry because of its excellent biocompatibility, osseoconduction and osseointergration. The only problem with pure HA is brittle. Because of this many modifications have been done by scientists to develop a stronger and biocompatible ceramic material especially for bone replacement. Our stronger value added HA has been developed for biocompatibility testing which is cytotoxicity test. In this study we tested this valued added HA for its cytotoxicity against lung embryonic fibroblast cell line (MRC-5).We found that value added HA slightly toxic compared to pure HA. Several recommendations for the scientists and clinicians for the future biocompatibility studies should be further carried out.Truly.