Who knows about the Bench community who have a long experience of cultivating yams and still bringing some of the wild types of yams to their garden and starting to domesticate them. who knows the wild yam types found in the jungles of the tropical forest found in Bench-Maji Zone, South Western Ethiopia. Yes, this society has an exciting knowledge of yam diversity management.They know how to classify yams. Even though some yam landraces are already lost and some are on the verge of diapearance,still the Bench society are struggling to maintain what is remained in their hand. Dear reader, you may be an agriculturalist or any person who worried about the loss of diversities. Do you want to understand if what are the determinants of yam landrace diversity in Bench society.If so, read this thesis. You will get important informations that will help you in your effort to understand the issues raised above. Thank you for trusting me and reading this thesis.