Phacelia is a multiannual herbaceous plant, which was introduced into cultivation in the Republic of Moldova in the middle of the 20th century, with the construction of industrial animal complexes, being among the 20 beneficial plants that attract insects. In 2023, on the territory of the "Plaiul Fagului" Reserve, for the first time, a field with phacelia was sown. The aim of the work includes the study of the diversity of some invertebrates in the phacelia plot and in the adjacent biotopes on the territory of the "Plaiul Fagului" Reserve. As a result of the study, a total of 60 insect species were identified, including 10 species of dragonflies, 39 species of cicadas and 11 species of ladybirds. Two species of ladybirds (Scymnus apetzi and Scymnus haemorrhoidalis) and one dragonfly (Aeshna mixta) are cited for the first time for the reserve. The research was carried within the project 20.80009.7007.02 EVOLANTER.