This paper presents a revision of the genus Dyscia Hübner, [1825] (Lepidoptera, Geometridae: Ennominae). Examination of types and additional material for most described taxa has resulted in several new synonyms: Dyscia ilivolans Wehrli, 1953 syn. n. and Dyscia duanjiao Yang, 1978 syn. n. are new synonyms of Dyscia fagaria (Thunberg, 1784); Dyscia karsholti Wiltshire, 1991 syn. n. is a new synonym of Dyscia galactaria Turati, 1934; Dyscia dagestana Wehrli, 1934 syn. n. is a new synonym of Dyscia malatyana Wehrli, 1934, and Dyscia rjabovi Wardikjan, 1957 syn. n. is a new synonym of Dyscia negrama Wehrli, 1953. One taxon, formerly treated as a species is reassigned to subspecific level, Dyscia conspersaria ssp. sultanica Wehrli, 1936 stat. rev. Dyscia innocentaria sicanaria (Oberthür, 1923) stat. n. and Dyscia malatyana senecai Wiltshire, 1990 stat. n. are downgraded to subspecies-level. On subspecies-level, Dyscia distinctaria perdistincta Herbulot, 1957 syn. n. is a new synonym of Dyscia distinctaria (Bang-Haas, 1910), Dyscia fagaria alvarensis Wahlgren, 1913 syn. n., Dyscia fagaria albescens Lempke, 1952 syn. n., Dyscia fagaria fusca Lempke, 1952 syn. n., and Dyscia fagaria postdelineata Lempke, 1952 syn. n. are new synonyms of Dyscia fagaria. Dyscia fagaria psoricaria (Eversmann, 1848) syn. n. is a new synonym of Dyscia fagaria favillacearia (Hübner, [1799]), Dyscia holli duponti Thierry-Mieg, 1910 syn. n. is a new synonym of Dyscia holli (Oberthür, 1910), Dyscia malatyana nachadira Brandt, 1941 syn. n. and Dyscia malatyana theodoraria Warnecke, 1941 syn. n. are new synonyms of Dyscia malatyana albersaria Warnecke, 1940 stat. n., and Dyscia penulataria naevata Wehrli, 1953 syn. n. is a new synonym of Dyscia penulataria (Hübner, [1819]). Lectotypes for 22 taxa and neotypes for three taxa - Geometra conspersaria [Denis & Schiffermüller], 1775, Geometra favillacearia Hübner, [1799], and Geometra emucidaria Hübner, [1813] - are designated. One species is excluded from Dyscia, Thysanopyga serena (Dognin, 1906) comb. n. From a total of 72 previously described taxa, 19 are recognized as species.