The species belonging to the genus Eurygaster Laporte are very important from the economic point of view in Turkey. Eurygaster integriceps Puton is one of the most harmful insects to wheat and barley, but in addition it also attacks rye, oat and other graminaceous plants. In Turkey it causes extensive damage especially in the eastern south provinces, the amount of injury caused varying from year to year and from place to place. In epidemic years the total amount of the losses in some areas can reach up to 9o% if no control measures are used. Eurygaster maura (L.) and Eurygaster austriaca (Schrk.), found especially in Western Anatolia, cause damage approaching only 20% if no control measures are used, because their egg parasites are very active in this part of the country. A good knowledge of this genus is therefore very important to Turkish entomologists and agriculturists. While working at the University of Aegea, Izmir-Turkey, I paid speciaL attention to these insects and collected many specimens whenever time was available. Amongst my material I find one new species which is described below.