Coated particles according to the present invention are comprised of particles each having a surface. At least the vicinity of the surface of the particle is constituted of a calcium phosphate-based compound. The particles are coated with a polyamine-based compound, and an average particle size of the particles is 1 μm or more. Furthermore, such coated particles are produced by preparing a preparation liquid containing a liquid containing at least one of water and an alcohol, the coated particles and the polyamine-based compound and then heating the preparation liquid to coat the particles with the polyamine-based compound. Furthermore, it is preferred that the liquid used in preparing the preparation liquid contains methanol as a main component thereto.