The genus Gasteruption Latreille, 1796 (Hymenoptera: Evanioidea: Gasteruptiidae: Gasteruptiinae) from North Iran and Turkey is revised, keyed and fully illustrated for the first time. In total 36 species are treated of which 33 are recorded from Turkey and 23 from Iran. Fifteen species are new for science: Gasteruptionaciculatum van Achterberg, sp. n., Gasteruptionagrenum van Achterberg, sp. n., Gasteruptionbrevibasale van Achterberg & Saure, sp. n., Gasteruptioncoriacoxale van Achterberg, sp. n., Gasteruptionflavimarginatum van Achterberg, sp. n., Gasteruptionheminitidum van Achterberg, sp. n., Gasteruptionhenseni van Achterberg, sp. n., Gasteruptionischnolaimum van Achterberg, sp. n., Gasteruptionnigrapiculatum van Achterberg, sp. n., Gasteruptionpaglianoi van Achterberg & Saure, sp. n., Gasteruptionpseudolaticeps van Achterberg, sp. n., Gasteruptionpunctifrons van Achterberg, sp. n., Gasteruptionschmideggeri van Achterberg & Saure, sp. n., Gasteruptionscorteum van Achterberg, sp. n. and Gasteruptionsmitorum van Achterberg, sp. n. Twenty-one species are reported new for Turkey and 16 species new for Iran. Fifteen new synonyms are proposed: Foenusterrestris Tournier, 1877, Gasteruptiontrifossulatum Kieffer, 1904, and Gasteruptionignoratum Kieffer, 1912, of Gasteruptioncaucasicum (Guérin-Méneville, 1844); Gasteruptiondaisyi Alekseev, 1993, of Gasteruptiondolichoderum Schletterer, 1889; Gasteruptionassectatorvar.nitidulum Schletterer, 1885, of Gasteruptionfreyi (Tournier, 1877); Gasteruptionschossmannae Madl, 1987, of Gasteruptionhastator (Fabricius, 1804); Gasteryptionfallaciosum Semenov, 1892, Gasteruptiondubiosum Semenov, 1892 and Gasteruptionobsoletum Semenov, 1892, of Gasteruptioninsidiosum Semenov, 1892; Gasteryptionschewyrewi Semenov, 1892, of Gasteruptionjaculator (Linnaeus, 1758); Gasteruptionfloreum Szépligeti, 1903, of Gasteruptionlugubre Schletterer, 1889; Gasteruptiontrichotomma Kieffer, 1904, and Gasteruptionpalaestinum Pic, 1916, of Gasteruptionmerceti Kieffer, 1904; Gasteryptionfoveiceps Semenov, 1892, of Gasteruptionnigrescens Schletterer, 1885, and Gasteruptionlibanense Pic, 1916, of Gasteruptionsyriacum Szépligeti, 1903. Gasteruptionlugubre Schletterer, 1889, is recognised as a valid species. Lectotypes are designated for Ichneumonassectator Linnaeus, 1758; Ichneumonjaculator Linnaeus, 1758; Foenusterrestris Tournier, 1877; Foenusfreyi Tournier, 1877; Foenusnigripes Tournier, 1877; Foenusgoberti Tournier, 1877; Foenusgranulithorax Tournier, 1877; Foenusminutus Tournier, 1877; Foenusborealis Thomson, 1883; Faenusdiversipes Abeille de Perrin, 1879; Foenusrugulosus Abeille de Perrin, 1879; Faenusobliteratus Abeille de Perrin, 1879; Faenusundulatum Abeille de Perrin, 1879; Faenusvariolosus Abeille de Perrin, 1879; Gasteruptiondistinguendum Schletterer, 1885; Gasteruptionlaeviceps Schletterer, 1885; Gasteruptionthomsonii Schletterer, 1885; Gasteruptionfoveolatum Schletterer, 1889; Gasteruptionsowae Schletterer, 1901; Gasteruptionfoveolum Szépligeti, 1903; Gasteruptionfloreum Szépligeti, 1903; Gasteruptioncaudatum Szépligeti, 1903; Gasteruptionsyriacum Szépligeti, 1903; Gasteruptionmerceti Kieffer, 1904 and Gasteruptionignoratum Kieffer, 1912. A neotype is designated for Gasteruptiontournieri Schletterer, 1885.
Keywords: Gasteruptiidae; Gasteruption; Iran; Revision; Turkey; key; lectotype designations; new records; new species; new synonyms.