THE OBJECTIVE of this article was to report diatom in aborted …… fetal membrane of cattle. Tissue samples of aborted fetal membrane were fixed in 10% neutral buffered formalin and submitted for pathological evaluation. The tissue samples were prepared for examination and stained with Hematoxylin and eosin, Gram, Gomori's methenamine-silver and Periodic Acid Schiff, and examined using research and phase - contrast microscope. Histopathological examination showed different shapes of diatoms. The most common type of diatoms in the examined tissues was reported. In conclusions, this report is considered the first detection of diatoms in a tissue of aborted fetal membrane of a dairy cows. The source of infection may be from drinking contaminated water, however no pathological changes could be detected around diatoms and the relationship between abortion and algae infection was not detected and further studies were carried out regarding this point.