The invention discloses a chlorine dioxide disinfectant special for livestock and poultry, which belongs to the technical field of disinfection. The product is prepared from the following raw materials in parts by weight: chlorite, monopersulfate, an acidifying agent, bromide salt, a stable forming agent and a drying agent. The chlorite is at least one of alkali metal salt of chlorite and alkalineearth metal salt of chlorite; the acidifying agent is at least one of sodium hydrogen sulfate, sodium bicarbonate, potassium bicarbonate and boric acid; wherein the bromide salt is selected from at least one of sodium bromide, lithium bromide, potassium bromide, calcium bromide, magnesium bromide, ammonium bromide and aluminum bromide; wherein the stable forming agent comprises at least one of sodium sulfate, magnesium sulfate, magnesium hydroxide, sodium chloride and magnesium chloride; and the drying agent is at least one of calcium chloride, calcium sulfate and calcium stearate. The invention also provides a preparation method of the disinfectant. The disinfectant does not generate substances such as chloroform and cyanuric acid in the activation process, so that the disinfectant is suitable for occasions such as livestock and poultry breeding.