The invention relates to an IgA (Immunoglobulin A) antibody detection reagent kit (a colloidal gold method) for EB (Epstein-Barr) viruses and a preparation method thereof. The reagent kit comprises recombination antigen EB-NA1 coated by a nitrocellulose membrane detection line, a goat-anti-mouse IgG antibody coated on a quality control line and a mouse-anti-human IGA monoclonal antibody marked by colloidal gold and coated on a gold mark pad. The preparation method comprises the steps of: preparing a reaction membrane and a mouse-anti-human IGA monoclonal antibody gold combo pad, cutting and assembling to prepare the product. The invention has the advantages that: the IgA antibody detection reagent kit for the EB viruses has the characteristics of fast, simple and convenient detection, and high accuracy and sensitivity; the integrated operation time only requires 20 minutes to judge and read results; the colloidal gold is used for fast detecting test paper; a multi-epitope recombination antigen is used as a raw material; the method has the characteristics of simple and convenient operation, low cost, good specificity, high sensitivity, single portion detection and easy popularization; and the detection and control effect to the EB viruses is obvious.