In tissue engineering, biodegradable scaffolds are basically used to provide temporary mechanical strength and necessary ions for the growth of bone. A bone scaffold has to have acceptable biocompatibility, controlled degrade rate and mechanical strength in order to support cell adhesion and cellular differentiation so as new bone can be properly substituted at the end. The aim of this study is to synthesis Nano powders of ? and ? tricalcium phosphate and Strontium fluorapatite; and applies them to fabricate composite scaffold with proper strength. To this aim, both ? and ? TCP powders were synthesized through two different routes for each one and characterized. Finally, the water solvent method and Si-?TCP were utilized respectively for further research. Studying of TEM images of ? and ? TCP powders reveals that their particle size is less than 100 and 15 nm, respectively. Furthermore, SrFAp powders were synthesized by the mechanical alloying method. Then they were characterized according to tests such as Rietveld refinement of XRD and bioactivity which illustrated that the substituted Sr does not affect the formation of bone like apatite in bioactivity tests. In order to fabricate the ceramic scaffolds, gel casting and polymer sponge method were both used at first, then the latter method -polymer sponge method- was selected due to its easier controllability and higher open porosity percent. Different compositions of the above powders were applied to fabricate composite scaffolds by the use of the polymer sponge method. The scaffolds were characterized according to compression, measuring porosity and soaking in simulated body fluid tests. The results showed that porous scaffold with the strength of about 6 Mpa could be fabricated by the use of ?TCP powder. Moreover, considerable increase in the strength of the scaffold which was more than 30 percent was observed by adding SrFAp to TCP powders. Finally, scaffolds with ability to be controlled in different parts as to their composition and porosity were fabricated, which make it possible to simulate physical appearance of the bone as well as to have acceptable control over the biological properties in different areas. Keywords: ? tricalcium phosphate, ? tricalcium phosphate, Sr fluorapatite, Tissue engineering, Nano particle, Rietveld Refinement, porous ceramic.