Abstract: Bacterial wilt (Ralstonia solanacearum) is the second most important biotic constraint to potato production after late blight in Kenya. The study was conducted to asses Irish potato cultivars’ tolerance to bacterial wilt. Determination of potato reaction to bacterial wilt was carried out in fields infested with R. solanacearum in two sites in Kenya using five cultivars; Tigoni (CIP-381381.13), Asante (CIP-381381.20), Kenya Karibu, Kenya Sifa and Dutch Robjyn were used. The experiment was laid out as a randomized complete block design. Disease related data were then recorded during the study period. Tubers from plants that appeared healthy during the study period were sampled and tested for latent infection using the enzyme linked immunosorbent assay on nitrocellulose membrane (NCM-ELISA). Data was subjected to analysis of variance and t-test. Subsequently, potato tolerance to bacterial wilt was determined by use of a regression model and ranking. None of the potato cultivars was found to be tolerant to bacterial wilt but some cultivars showed some level of tolerance. Reaction of potato cultivars’ to bacterial wilt was variable in the two environments and even within the same environment. The cultivars Kenya Sifa was the most tolerant while Dutch Robjyn was the most intolerant. The use of these tolerant cultivars together with other control strategies could alleviate the disease problem significantly.