The invention relates to an annular fluidized bed separator of a particle mixture. The upper end of a center lifting pipe extends into an annular fluidized bed by a certain height, so that the annular fluidized bed is divided into an annular area at the lower part and a cylindrical area at the upper part; an air inlet and a wind distribution plate are respectively arranged at the bottoms of the center lifting pipe and the annular fluidized bed; a feed port is formed in the bottom of the center lifting pipe; a heavy particle outlet is formed in the bottom of an annular area of the annular fluidized bed, and is connected with a heavy particle collecting tank; and an airflow outlet at the top of the annular fluidized bed is connected to a light particle collecting tank by a cyclone separator. The particle mixture is quickly fluidized in the center lifting pipe for primary dispersion, and is ascended along with air currents to enter the annular fluidized bed for secondary dispersion. The annular fluidized bed separator can continuously and quickly perform high-efficiency separation for light and heavy particle mixtures under the condition of normal temperature or high temperature. The annular fluidized bed separator can be coupled with a circulating fluidized bed reactor system, and can continuously and stably operate.