The invention relates to the field of closestools, in particular to a water-saving closestool which comprises a closestool base, a pedestal, a gasket, a closestool cover, a water tank, a first water outlet connector, a second water injection connector, a first electromagnetic valve, a second electromagnetic valve, a first water inlet connector, a second water inlet connector, an activated carbon containing box, an activated carbon bag, a cover plate, air holes, a box body, a partition plate, a cleaning solution containing area and a disinfectant containing area. The closestool comprises a disinfecting and cleaning mechanism; a cleaning solution and a disinfection solution can be contained in the cleaning and disinfection mechanism box body; after the toilet is flushed once, water is injected into the water tank; liquid in the tank body flows into the water tank and is mixed with water injected into the water tank, so that the closestool can be flushed more cleanly and bacteria and thelike in the closestool can be killed at the same time after a user goes to the toilet and flushes water, the bacteria breeding condition in the closestool is greatly avoided, the sanitation of the closestool is improved, and the health of the user is improved; the peculiar smell adsorption mechanism of the device can adsorb most peculiar smell in the closestool, and the quality of the environmentin the toilet can be improved.