Abstract: In Hungarian forest, semiochemicals are employed for monitoring and mass-trappingof pest insects. Pheromone monitoring could be successfully used for several lepidopteranspecies (e.g. Lymantria dispar, Coleophora laricella). To date, about 40 pheromone compoundsare available for forest Lepidoptera. Aggregation pheromones (approximately 20 compounds) arewidely used for mass trapping of bark and wood boring insects (e.g. Ips typographus, Pityogeneschalcographus). The forest protection practice is primarily focused on mass trapping of barkbeetles, while the application of pheromones of lepidopteran and other insect species is ratherrare, mainly for scientific purpose.