In the current study, karyotypes of four taxa in the genus of Ornithogalum L. were examined. These taxa grow naturally in Eskisehir (Central Anatolia). Studies were carried out on somatic chromosomes, using the root tips squash technique and based on staining with acetic orcein stain, for the most actively dividing meristematic cells of the collected root tips. Their counts were based on chromosomes observed during mitotic division. For species included in the Ornithogalum L. (Asparagaceae) genus, O. montanum Cirillo has 2n = 14 with basic chromosome number x = 7; O. comosum L. has 2n = 20, basic chromosome number x = 10, O. pyrenaicum L. has 2n = 24, basic chromosome number x = 12; and O. sigmoideum Freyn & Sint. has 2n = 14, basic chromosome number x = 7; it was found that they have diploid chromosomes. O. montanum and O. sigmoideum chromosome numbers are 2n = 14 (diploid races), but their basic karyotypes are different, including chromosome size, and position of centromere. Mean chromosomal length of the all taxa subject to the study is 1.20-7.63 mu m. Chromosomal morphologies of all taxa include median, submedian and subtelocentric chromosome pairs. In addition to, karyograms and idiograms of all studied taxa were done.