The invention discloses a cutting fluid filtering device for a numerically-controlled machine tool. The cutting fluid filtering device for the numerically-controlled machine tool comprises an installing frame. The top of the left side of the inner wall of the installing frame is fixedly connected with a waste liquid box. The top of the waste liquid box is fixedly connected with a stirring motor. Through mutual cooperation of the waste liquid box, the stirring motor, a stirring shaft, a stirring part, a waste liquid pump, a waste liquid sucking pipe, a waste liquid outlet pipe, a filtering head, a filtering box, a filter, a filtering layer, an adsorption motor, an adsorption shaft, an adsorption part, a spraying box, an adsorption layer and a spraying pump, the filtering effect of the cutting fluid filtering device for the numerically-controlled machine tool is better, scrap iron and scum mixed in cutting fluid in the workpiece machining process of the numerically-controlled machine tool can be filtered and separated in time, impurity residues in the cutting fluid are effectively filtered out, and the phenomenon of deterioration of the cutting fluid caused by accumulation of too many impurities is prevented. Therefore, the secondary use performance of the cutting fluid is improved, and a workpiece and a tool are protected.