The invention relates to a method for preparing a reagent plate for detecting sulfanilamide medicine residue in honey, for detecting sulfanilamide medicines in agriculture products such as honey. The reagent plate consists of an upper plastic template, a lower plastic template and a backing, wherein a sample pad, a colloidal gold combining pad, a nitrocellulose membrane and a water absorbing pad are sequentially adhered to the backing tightly; a detection line and a quality control line are sequentially sprayed on the nitrocellulose membrane in the direction from the sample pad to the water absorbing pad, and then reaction result can be represented in color visible for naked eyes. By adopting the reagent plate, semiquantitative visible detection can be performed, the whole operation process only takes 20-30 minutes, and moreover no expensive experiment equipment is needed, so that on-scale sample screening is facilitated, and the method is applicable to on-scale rapid detection on sulfanilamide medicines in raw materials and products for industry and commerce departments, inspection and quarantine institutions and agricultural product production and machining companies.