Two methods of estimation of potato cultivars for resistance to the agent of brown bacterial rot (Ralstonia solanacearum) were used. The distribution of the most widespread agricultural zoned potato cultivars into groups depending on the degree of their resistance to bacterial quarantine agent, potentially dangerous for Ukraine, can be used in the selection of the potato varieties resistant to the agent, and in the development of integrated plant protection systems. R. solanacearum was not detected in the potato samples from Chernovtsy and Kyiv Regions. However, agricultural zoned Ukrainian Solanaceae cultivars are sensitive to the collection R. solanacearum strains. Therefore, the agent is potentially dangerous and requires continuous control over its appearance and propagation.