A technology for protecting a valve seat inside a collection tank from the adherence of frozen particles in a vacuum freeze-drying apparatus and a frozen particle manufacturing method. The inside of a vacuum tank and a collection tank are vacuum evacuated； a raw material liquid is injected into the vacuum tank to produce frozen particles； and the frozen particles are piled up on a surface of a heating/cooling shelf. When the frozen particles on the heating/cooling shelf are transferred into the collection tank through the inside of an auxiliary pipe, the frozen particles do not adhere to a valve seat which surrounds an opening of a main pipe inside the collection tank.
