The invention discloses a device for regenerating and layering mixed-bed resin, which consists of a mixed-bed water inlet device, a drainage device, a regeneration device, a water distribution device,an air exhaust valve, a compressed air inlet valve, and a low-frequency sound wave generator. The compressed air inlet valve, the low-frequency sound wave generator, the water distribution device, and the air exhaust valve are arranged in series from bottom to top;during backwashing layering, a backwashing water inlet valve and an upper middle drain valve are opened,after water comes out of the upper middle water drain valve, the backwashing water inlet valve and the upper middle drain valve are closed, then the compressed air inlet valve is opened, the low-frequency sound wave generator starts working, exhaust of the low-frequency sound wave generator is differentiated into tiny uniform bubbles when passing through the water distribution device, the bubbles enter the bottom of a resin layer and lift the resin layer up, low-frequency sound waves enter the resin layer through small holes of the water distribution device, the oscillation of the sound waves repeatedly acts on the resin layer to be floated up and down together with a liquid medium, the loosened resin layer reaches a certain expansion ratio, and the true density difference of anion and cation resinsin a wet state is used for achieving the purpose of layering.