Disclosed is a treatment system for removing iron-aluminum-chromium reaction products in leaching solution of laterite nickel ore, comprising a reaction tank, a lifting assembly, a flushing assembly, and a receiving box. The lifting assembly comprises a rotating shaft, a net pouch, and a connecting rod. The rotating shaft is rotatably connected to the reaction tank and is connected to the net pouch via the connecting rod; the rotation path of the net pouch covers and adheres to the inner bottom wall of the reaction tank, and it can be rotated to a first position and a second position; when the net pouch rotates to the first position, the opening of the net pouch is inclined upwards; when the net pouch rotates to the second position, the opening of the net pouch is inclined downwards; flushing end of the flushing assembly is directed at the opening of the net pouch in the first position. the receiving box can slide to a position directly below the net pouch at the second position. This solution addresses the current issues of requiring multiple thickeners for solid-liquid separation, which results in large equipment size and inconvenience in use.