Yam is the common name for some plant species in the genus Dioscorea (familyrnDioscoreaceae) that form edible tuber. Yams are herbaceous or dioecious annual orrnperennial vines cultivated for their edible starchy tuber in Africa, Asia, Latin Americarnand Caribbean. Yam production is negatively affected by pests and diseases in thernworld. Among these, virus diseases are the most important concerns of yam productionrnas they strictly restrict the exchange of germplasms for various purposes in breedingrnprograms. Among viruses reported to be infectious of yam crop in the world the genusrnPotyvirus is the largest group of viruses in Potyvirideae family and is the mostrnwidespread pathogen of yam virus diseases in the world. Yam mosaic virus (YMV) andrnYam mild mosaic virus (YMMV) are the two commonly reported Potyviruses to bernwidespread across yam growing areas of tropics and subtropics. This study wasrntherefore designed to detect Yam mosaic and Yam mild mosaic Potyviruses in majorrnyam growing areas of South-Western part of Ethiopia. ACP-ELISA, DAS-ELISA andrnRT-PCR were used to test a total of 336 yam leaf samples collected from JimmarnAgricultural Research Center, Bako Agricultural Research Center and HawassarnAgricultural Research Center for the two common Potyviruses (YMMV and YMV).rnAmong 336 total samples tested in this study 40 (12%) and 32 (9.5%) of them werernfound positives for potyvirus in ELISA and RT-PCR tests respectively. YMV wasrnfound in 30 (75%) and 38 (95%) of samples confirmed positive for potyvirus via DASELISArnand RT-PCR respectively, whereas YMMV is detected in none of the samples.rnThis study therefore provides valuable information about YMV, to be the importantrnPotyvirus attacking yams in Ethiopia, and is required to devise effective methods for therncontrol of YMV disease on yams.