Chamomiles (Anthemis, Matricaria, Tanacetum) are of the genus Choseni or Citrus (Compositae) whose species are precious to medicinal herbs and are distributed in different regions of Iran. In this study, the shape and structure of chromosomes by microscopic observation and using specific staining methods, was performed on 21 populations belonging to three genera of Anthemis, Matricaria and Tanacetum, collected from different parts of Iran. For this purpose, the seeds were first cultured on petri dish and transferred to 25 ° C after sterilization. After germination, the roots were pretreated with 1% Alphabromonphthalene and then fixed with Luttski solution. NaOH was used for normal hydrolysis and to stain the Sthhmothoxylin. Microscopic specimens were prepared by squash method and then studied using an optical microscope BX41 Olympus with a magnification of 1750 ×. In all samples, the chromosome base number was x = 9 and the ploidy level (diploid) = 18 = n2 = x2. In all populations, metacentric chromosomes were predominant, and in addition to metacentric Sub Metacenter and Subtwostrater chromosomes, were observed as well.