Symptoms consistent with citrus canker were observed in many citrus groves located in different egyptian citriculture regions. the presence of the disease was confirmed using different diagnostic methods. attempts to pathogen isolation from symptomatic citrus samples enabled toobtain15 bacterial isolates with characteristics consistent with xanthomonas citri subsp. citri. the results of physiological and biochemical tests supported the membership probability of these isolates to x. citrisubsp. citri. pathogenic response of these isolates was established by artificially inoculation of detached and attached leaves of grapefruit and valencia sweet orange. all isolates caused canker symptoms on both citrus species. subjection of the isolates to omnilog id system indicated that, the isolates strongly belong to xanthomonas citri subsp. citri with similarity around 90 %. the identity of the isolates was confirmed by pcr amplification using primers 2-3. the pcr amplification successfully amplified a 222 bp dna fragment from all isolates except one. considering the results of the performed tests, these bacterial isolates confirmed to be x.citri subsp. citri and accordingly, the symptoms that appeared on the affected trees represented citrus canker disease .in another trend, some epidemiological features of the disease were studied. the obtained isolates significantly varied in their aggressiveness. the disease was occurred in 31.7 %of surveyed groves which were distributed in all surveyed localities. disease incidence (number of symptomatic trees) within diseased groves recorded 8.49%. the total mean of disease severity on the diseased trees within localities reached 35.75%.