Water treatment agent and water treatment method

The invention relates to the field of water treatment. A water treatment agent disclosed by the invention comprises a flocculant and a disinfector in a mass ratio of (5-50): 1, wherein the flocculant comprises ferric sulfate, bentonite, chitosan and polyacrylamide; the disinfector is one or two of calcium hypochlorite and potassium permanganate. The ferric sulfate, bentonite, chitosan, polyacrylamide and the disinfector are compounded to form a gel with a flocculation effect, wherein the gel can play roles of flocculation, sedimentation and disinfection at the same time, so that common compound pollutants such as protozoans, bacteria, parasites, organic matters, heavy metals and the like in a rural drinking water source can be effectively removed at the same time, the chromaticity and turbidity of water are reduced, and the treatment effect is good.