The research on the impact of useful and pathogenic entomofauna affecting valuable plant species, with melliferous, fodder, medicinal potential etc., can bring a significant contribution to the agriculture of the Republic of Moldova. The species Reynoutria sachalinensis (F. Schmidt) Nakai is known as a perennial, nontraditional fodder plant with multiple utility, attractive to insects. The research carried out in the "Alexandru Ciubotaru" National Botanical Garden (Institute) highlighted the presence of a large number of insect species on the vegetative and generative organs of R. sachalinensis plants, throughout the growing season, with maximum frequency and intensity in flowering phase. The Hymenoptera order was represented by 6 species of insects (Apis mellifera L., Scolia hirta Schrank, Formica rufa L., Lasius niger L., Katamenes arbustorum Penzer, Athalia rosae L.) classified in 6 genera (Apis, Scolia, Formica, Lasius, Katamenes, Athalia) and 5 families (Apidae Latreille, Scoliidae Latreille, Formicidae Latreille, Vespidae, Tenthredinidae Latreille). Valuable melliferous and pollinator insect species, with diverse trophic spectrum – pollenophages, nectarivores, omnivores, predators. The maximum frequency during the entire flowering period was achieved by the representatives of the Apis mellifera species, an indispensable element of beekeeping.