A calcium phosphate-synthetic resin composite body produced by pressing a calcium phosphate block (or a calcium phosphate block and calcium phosphate particles), and synthetic resin particles I, which are at least partially cross-linked in advance, and uncross-linked, synthetic resin particles II while heating, the calcium phosphate block being exposed on at least part of the surface of the composite body. The above composite body is produced by a method comprising the steps of (a) introducing the calcium phosphate block (or a calcium phosphate block and calcium phosphate particles), the synthetic resin particles I and II into a cavity of a forming die such that the calcium phosphate block is present on at least part of the surface of the composite body, and that the synthetic resin particles surround the calcium phosphate particles, if any; and (b) pressing them in the cavity of the forming die while heating, so that the synthetic resin particles are bonded to each other.