Peanuts were screened for aflatoxin using a rapid, inexpensive fluorometric method. Peanuts were ground and extracted with methanol, and the extract was treated with acidified zinc-acetate-sodium chloride solution, filtered, and diluted with water. Fluorescence of the extracts was compared with that from aflatoxin-free control peanuts. Test samples (160) of several varieties and grades of sources and were screened for the presence of aflatoxin. One hundred thirty-five samples (84%) were identified by this method as aflatoxin positive (15 ppb+) or aflatoxin negative (<15 ppb). Although 22 samples (13.6%) were incorrectly labeled as aflatoxin positive, most of these showed evidence of the presence of mold metabolites other than aflatoxin. Three samples (1.8%) were incorrectly labeled as aflatoxin negative when they actually contained 20, 33, and 34 ppb aflatoxin.