Disclosed is an internal circulation resin ion exchange adsorption reactor with a mechanical stirrer. The upper part ⅔˜⅘ of the reactor main body is an open cylinder and the lower part 1/5˜⅓ is a cone-shaped body with a slope of 30°±10°. A bell-jar shaped reaction slot with a turbine water stirrer inside is located in the center of the reactor main body. The reactor main body is equipped with a cylindrical guide plate. A water collection weir, an inclined tube separator and an annular resin collection hopper are located between the shell of the reactor main body and the guide plate. The reactor is equipped with a water inlet pipe and a water outlet pipe. A resin removal pipe is connected with the annular resin collection hopper and a resin desorption slot respectively, and a regenerated resin reflux pipe is connected to the bell-jar shaped reaction slot.