Abstract: The pollen morphology of 41 species belonging to tribe Trifolieae, 4 taxa to Ononis, 8 to Trigonella, 13 to Medicago, 4 to Mellilotus and 12 to Trifolium has been studied using both light and scanning electron microscopes. The results revealed that this tribe is stenopalynous with different pollen types. According to present data the species studied have been classified into three pollen types with five subtypes. These types not in accordance with the taxonomic divisions of these genera. General pollen descriptions of the genera as well as a discussion about the classification of the genera has been done. An evolutionary line according to pollen characters has been postulated.