The ultrastructure of the egg chorion of Nemoptera sinuata Olivier 1811 was studied with scanning (SEM) and transmission (TEM) electron microscopy. Females were collected from Antalya, Finike, Turkey, and maintained under laboratory conditions. Eggs were laid singly in cotton batting. The eggs are spherical, snow-white, and lusterless; with a diameter of 0.82-0.91 mm; and with one micropyle. The chorion is highly sculptured with regular hexagonal convexities on the surface touching one another. The micropyle is in disk form; in profile it resembles a cornet with no opening. In cross section, three layers of chorion are easily distinguished by transmission electron microscopy.