Whereas phenetics emphasizes the use of maximum characters as practicable, decisions on how observations are translated to characters is of importance in systematics in order to partition objects in to nonoverlapping groups.The acetolysed pollen of selected Indigofera Linn. species were viewed under Mg x100 in Leica light microscope. Pollen characteristics of the following Indigofera species deposited in Maseno University Herbarium have been studied: I.paracapitata, I.asparagoides, I.ambelacensis, I.vohemarensis, I.sabargentea, I.circinella, I.zenkeri, I.arrecta, and I.vicioides. The highest taxonomic diversity (0.5) was observed when aperture character and amb were separately used in two character states. Shape class in 2 character state coding gives the least phenotypic diversity (0.149). I.asparagoides is of the highest mean dissimilarity (0.563) to other species in all the characters coded into two character states. I. circinella had 44.7% dissimilarity to the rest of the species when characters in three states were used, and was the most dissimilar to the rest of the species when all the pollen characters were used in both their 2 and 3 states. There was a 36.6% and 35.6% taxonomic diversity with pollen characters in their two and three character states respectively