A lint filtering device (5) for a washing machine and the washing machine. The lint filtering device (5) is installed at the bottom of an inner tub (2), and the device is a self-cleaning filtering device which collects lint during washing and removes the lint by using water flow during draining. The present invention also relates to a lint filtering method for the washing machine: washing water in the inner tub (2) of the washing machine flows to the space between the inner tub and an outer tub from a dewatering hole arranged on a side wall (20) of the inner tub, and the lint in the washing water is filtered and collected in the process of returning the washing water to the inner tub (2) from the bottom of the inner tub (2); and when the washing machine drains water, the collected lint is removed by using the drained water flow and is discharged out of the washing machine along with the drained water flow. By means of the described configuration, the wall of the inner tub (2) forms a glossy surface, which red
