The invention provides a sulfur-containing bleacher rapid detection reagent for solving the technical problems generated in the detection process of a sulfur-containing bleacher at present. The detection reagent is prepared from 0.05%-0.07% of a pararosaniline hydrochloride reagent, 0.2%-0.4% of a formaldehyde reagent and 1.1%-1.3% of an ammonium acetate solution. A rapid detection method of the sulfur-containing bleacher is simple and easy to operate and can be used by non-professional personnel, an accurate detection result can be quickly obtained in half an hour after detection, the detected suspicious sample range can be narrowed to minimum, and the method is suitable for on-site operation.