Provided is a sustained releaser of a sex pheromone having a high release rate, especially preferably of a sex pheromone of an aliphatic acetate compound having 10 to 16 carbon atoms, wherein the release of the sex pheromone is controlled so that it can be released at a constant rate over a control period of a pest insect. More specifically, provided is a sustained pheromone releaser comprising a polymer container and having, enclosed therein, a mixture having a melting point of 15 to 35° C. and being obtained by mixing a sex pheromone substance and a compound having a melting point of 10 to 40° C.