The invention provides a drainage device of a washing
machine, the washing
machine and a control method of the washing
machine. The washing machine comprises an inner
barrel and a water collecting device, drainage holes are formed in the bottom of the inner
barrel, the place between the inner
barrel and the water collecting device is free from water during washing, and the water in the inner barrel enters the water collecting device to be drained in the drainage and
dehydration process; the drainage device comprises a sealing mechanism and a
locking mechanism, the sealing mechanism comprises aplugging component and a driving component, wherein the plugging component is mounted on a drainage port to keep the drainage port normally closed, the driving component is provided with an output end which reciprocates along the direction parallel to the central axis of the inner barrel; and the
locking mechanism locks and positions the inner barrel, the output end of the driving component reciprocates, and the plugging component is ejected out to open / reset to close the drainage holes; the water collecting device is provided with a common mounting part for mounting driving components of thelocking mechanism and the sealing mechanism at the same time.