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Rice is the major food crop in Myanmar and bacterial blight is one of the devastating diseases affecting production. In this study, 37 local rice varieties and 41 rice lines were tested at Yezin Agricultural University, Myanmar, to three different isolates of Xanthomonas oryzae pv. oryzae to evaluate the resistance levels of these different rice varieties. The three bacterial isolates used in this experiment were collected from Zeyathiri, Zabuthiri and Pyinmana townships in Nay Pyi Taw Union Territory. At maximum tillering stage, the uppermost fully expanded leaves were inoculated by the clipping method. Three weeks after the inoculation, the percent leaf area of the inoculated leaves was visually estimated and the disease reaction of the rice varieties determined. The thirty-seven local rice varieties were classified into seven groups, with this grouping based on the reaction patterns to the three isolates. Group VII, which contained two varieties, Nga Sar Kay and Sinthukha, was moderately resistant to Pyinmana isolate and moderately susceptible to the Zeyathiri and Zabuthiri isolates. The rice varieties included in Group I to Group VI showed susceptible reactions to testing with all three isolates. Among YAU rice lines tested, YAU-1211-71-1-1 exhibited moderate resistance to the Pyinmana isolate only. Apart from the line mentioned above, all the other YAU rice lines, did not exhibit resistance reactions to the test isolates. Nga Sar Kay, a local rice variety, has the potential to be used in the future rice breeding programs and YAU-1211-71-1-1 is the promising one to be used in areas where rice bacterial blight disease is prevalent. [ABSTRACT FROM AUTHOR]