During ovipositor dragging following egglaying in hawthorne fruit, females of Anastrepha suspensa (Loew) were found to deposit on the fruit surface an unidentified pheromone deterring repeated oviposition attempts in that fruit. The pheromone proved water-soluble, and when collected and sprayed in aqueous solution onto un infested fruits in laboratory cages, effectively deterred boring attempts by A. suspensa for at least 6 days (= termination of test).