This study was conducted between 2019-2020 in Erzincan Province Çayırlı District to reveal beneficial and harmful species and the biology of Spodoptera exigua (Hbn.) (Lepidoptera: Noctuidae), which is an important pest in sugar beet cultivation area. The study area designated as “Erzincan Çayırlı Beet Production Area” (EÇPÜA) has many beet cultivation areas. The beet production obtained from these beet fields changes according to the years, but is also noteworthy for both the region and our country. This area, sugar beet does not only bind the farmers to their field and their villages, provide work and employment opportunities to all family members, but it also is an important plant with its by-products all of which are processable. At the end of the study, five different harmful insect species belonging to the orders Orthoptera, Hemiptera, Coleoptera, Lepidoptera and 22 species [Coccinella septempunctata Linnaeus, Hippodamia variegata (Goeze), Psyllobora vigintiduopunctata (Linnaeus), Syrphus sp., Sphaerophoria scripta (Linnaeus), Sphaerophoria turkmenica Bankowska, Eristalinus aeneus (Scopoli), Tipula sp., Cotesia glomerata (Linnaeus), Exeristes roborator (Fabricius), Endromopoda phragmitidis (Perkins), Enicospilus merdarius (Gravenhorst), Exetastes laevigator (Villers), Itoplectis viduata (Gravenhorst), Exetastes laevigator (Villers), Itoplectis viduata (Gravenhorst), Lissonota (Loxonota) histrio (Fabricius,) Lissonota (Loxonota) flavovariegata Lucas, Ophion pteridis Kriechbaumer, Pimpla spuria (Gravenhorst), Scambus nigricans (Thomson), Scambus brevicornis (Gravenhorst), Sinophorus nitidus (Brischke) and Chrysoperla carnea (Stephens)] belonging to the orders Neuroptera, Coleoptera, Diptera and Hymenoptera were determined on the sugar beet plant. Among the pest species, the biology of the Spodoptera exigua (Hbn.), known as "caradrina" has been observed and the biological stages of the Agrotis segetum (Schiff.) which is in the secondary pest status have been followed. Damage patterns and densities of other pests (Cassida nebulosa Linnaeus, Aphis fabae (Scopoli), and Gryllotalpa gryllotalpa Linnaeus) were also tried to be revealed. Sinophorus nitidus (Brischke) collected in the study area which belonging to the family Ichneumonidae is determined as our new record for East Anatolia.