Stone fruits are an economically very important product especially in the eastern region of Turkey which is the biggest producer of dry and fresh apricot all over the world. Lake Van Basin is located in this region and it has a common border with Iran. In this respect, it is an important region for passing quarantine plant pathogens. Pseudomonas syringae pathovars were isolated in other regions of Turkey. But Xanthomonas arboricola pv. pruni has not yet been detected, and it is in the list of quarantine pathogens in Turkey. The goal of the this study was to determine the bacterial diseases on apricot, plum, peach, sweet and sour cherry trees in Lake Van Basin. Immature sweet cherry fruits were used for pathogenicity test. Sequence analysis of the 16S rRNA gene region was done using 27F and 1492R primers. Rhodotorula pilimanae strain MUCL 30397 and specific primers of cfl gene were used to determine the specific toxin - syringomycine and coronatin - production. Also, LOPAT and GATTa were used as other identification tests. In this study, 92 stone fruit orchards were visited and 69 suspect samples were collected. Bacterial pathogens were isolated from all provinces and districts in Lake Van Basin. Among the pathogens obtained there was no Xanthomonas axonopodis pv. pruni, and all of them were identified as Pseudomonas syringae pathovars. Two pathovars of Pseudomonas syringae were detected at the rate of 44% P. syringae pv syringae and 56% P. syringae pv. morsprunorum.