Provided is a method for disrupting mating of or controlling Tuta absoluta, a major tomato insect pest, by using a synthetic sex pheromone. Specifically, provided is a method for disrupting mating of Tuta absoluta comprising at least a step of releasing (E3, Z8, Z11)-3,8,11-tetradecatrienyl acetate into a space in which a density of the Tuta absoluta adults is 20 to 400 insects per 250 tomato plants and into which an invasion of Tuta absoluta adults from outside is prevented.
