Abstract: Parasitoid adults feed plant flower nectar for nutrition. To this end, the parasitoids need to recognize a sugar source as food. In the present study, preference of Trichogramma chilonis females for different colored flowers of Senecio cruentus and papers under illumination and whole dark conditions was investigated. Choice tests under illumination showed that white flowers of S. cruentus attracted 62.38% of T. chilonis, significantly more than pink, blue or fuchsia flowers and blank control. However, under the dark condition, no significant difference was found among all the treatments. Similar results were obtained for color papers in choice tests, white and pink papers attracted 59.83% and 40.69% of T. chilonis, respectively, significantly more than blue or fuchsia papers and blank control. Further analysis of choice response and color parameters showed that T. chilonis preferred high brightness (white and pink) color. Thus, flower color should be an important consideration in screening of appropriate nectar plants for improving the pest control performance of Trichogramma.