A rapid, nondestructive method of analyzing fluorescent dyes in fabrics is proposed, using surface fluorescence measurements. This method is applied in textile conservation. Woolen fabrics from the Museum and Archives at the Kyoto Institute of Technology were analyzed. These red fabrics, which originated from the Netherlands sometime between 1849 and 1857, were found to be dyed with cochineal. An unknown, nonfluorescent dye was also discovered in a pink sample.