The invention belongs to the technical field of test of carbonless copying papers, in particular relates to a quality testing reagent and method for microcapsules of carbonless copying papers. The quality testing method comprises the steps of: drying and grinding 5 to 30 parts of color developing agent into powder with the fineness of 5 to 20 Mum; dissolving the color developing agent which is ground into powder into 70 to 95 parts of pressure-sensitive dye solution, and mixing uniformly to prepare the color developing agent into a colorless transparent reagent; taking the carbonless copying papers needing to be tested during processing, dropping the reagent on one surface of the upper paper and the middle paper, coated with microcapsules, and observing whether the place dropped with the reagent is developed; if yes, determining that the microcapsules are broken after processing, have deficiency in quality, and need to be adjusted in tome; and if not, determining that the microcapsules are not broken after processing, and do not have deficiency in quality. The quality testing method is convenient to operate, is fast and effective, has a reliable testing result, and can effectivelyavoid quality problem of the carbonless copying papers in all the links during processing.