Hydroxyapatite is a bioceramic that can be used as a denture material. Hydroxyapatite can be produced by synthesizing blood clam shells and eggshells as a source of calcium and (NH4) 2HPO4, phosphate through hydrothermal methods. The hydroxyapatite samples were characterized by XRD and FTIR. The results of XRD analysis showed that the hydroxyapatite produced contained calcium carbonate (CaCO3) and apatite carbonate type A. Hydroxyapatite has a hexagonal structure with lattice parameters a = 9.404 Å and c = 6.675 Å the resulting crystal size ranges from 10.19 nm to 57.29 nm. The results of the FTIR spectrum of the hydroxyapatite sample contained functional groups PO4
3-, OH− and CO3
2- which are functional groups of hydroxyapatite.