Provided are core-shell particles which are kept stable in a solvent such as water for a long period. Each core-shell particle includes a core which contains a hydrophobic polymer having an anionic group and a shell which contains calcium phosphate. At least one of calcium atoms contained in calcium phosphate is chemically bonded to a functional group derived from the anionic group. In a method of manufacturing core-shell particles each core-shell particle includes a core which contains a hydrophobic polymer and a shell which contains calcium phosphate, the method includes the steps of: mixing a water-soluble organic solution which contains a hydrophobic polymer having an anionic group with a solution which contains calcium ion so as to obtain a first mixed solution; mixing the first mixed solution with a solution which contains phosphate ions so as to obtain a second mixed solution; and stirring the second mixed solution.