The present invention discloses a method of manufacturing pure dicalcium phosphate ceramics or dicalcium phosphate/hydroxyapaite (HA) biphasic ceramics for medical applications in hard tissue areas to be used as implant materials. These ceramic implant materials are in granular form or in block form, and are prepared by using an acidic phosphate compound, a basic calcium phosphate compound comprising HA, and water. The dicalcium phosphate ceramic comprises either dicalcium phosphate dihydrate (CaHPO4.2H2O, DCPD) or dicalcium anhydrous (CaHPO4, DCPA). Wherein, when the acidic phosphate compound is provided in an amount stoichiometrically equal to or in excess relative to the basic calcium phosphate compound, a reaction product is the DCPD or DCPA ceramic; when the acidic phosphate compound is provided in the amount stoichiometrically less than the basic calcium phosphate compound, the reaction product is the DCPD/HA or DCPA/HA biphasic ceramic.