Aim: This study was designed to evaluate the socket preservation using a synthetic nanocrystalline hydroxyapatite followed by collagen membrane. Subjects and methods: Fourteen patients were selected from Oral and Maxillofacial clinic of the Faculty of Oral and Dental Medicine, Al-Azhar University, Cairo, Boys. Extraction of tooth of lower premolar area was done to all participants. Then they were divided into 2 groups, where 7 sockets were preserved and the 7 were kept as control. After tooth extraction in the test group nanobone putty form was grafted into the socket. An additional covering was performed by a collagen membrane. A cone beam computed tomography (CBCT) radiograph at 3 and 6 months were done to assess bone density and socket dimensions. All readings were recorded and analyzed statistically. Results: Among the study group, there is a high statistically significant difference between the three measurements (soon after extraction, after 3-and 6-months from operation) as regards the mean of bone density and the three dimensions .Conclusion: Nano hydroxyapatite together with collagen membrane to seal the socket accelerates the formation of bone filling in the extracted bony socket