The effect of Ca(NO3)(2)center dot 4H(2)O and (NH4)(2)HPO4 primary solutions as the starting materials in the synthesis of a calcium phosphate phase was examined. Therefore, wet chemical reactions were investigated in solution at different temperatures by hydrothermal conditions aimed at hydroxyapatite (Ca-10(PO4)(6)(OH)(2), HAp) synthesis. The powders were investigated by XRD, SEM, FE-TEM, HRTEM, EDAX, SAED, and FTIR. It is found that the HAp have diameters of 25-50 nm and lengths of 120 +/- 30 nm with different morphologies. As a matter of fact, the hydrothermal method guarantees the production of HAp for different applications.