The responses of the egg parasitoid Trissolcus semistriatus (Nees) (Hymenoptera: Scelionidae) females to chemical cues from the plants: bread wheat Triticum aestivum L. (Poaceae), Lens culinaris Medik. (Fabaceae), Sinapis arvensis L. (Brassicaceae), Bifora radians Bieb. (Apiaceae) and Leontice leontopetalum L. (Berberidaceae), were investigated in the laboratory. Studies were carried out to determine the first reaction, the residence time and linear speed of the parasitoid using Y-tube and five armed olfactometers. In the Y-tube olfactometer experiments, T semistriatus showed the strongest responses to the odor of T aestivum with 86.7%, followed by L. leontopetalum with 80%. The parasitoids showed the weakest responses to the odor of B. radians with 26.7%. The residence times of T. semistriatus were determined as 87.53, 66.16, 53.50, 46.20 and 38.25 for T. aestivum, L. leontopetalum, L. culinaris, S. arvensis and B. radians, respectively. The linear speed was determined as significantly lower (3.81) in T. aestivum than in odors of the other plants. The linear speeds of L. leontopetalum, S. arvensis, L. culinaris and B. radians were determined as 4.66, 5.30, 5.14 and 6.92, respectively. The statistical analysis showed significant differences in the residence time in the plants. While the parasitoid was attracted mostly by T aestivum, the less attraction was caused by B. radians.