Pseudomonades, which causes ulcerative syndrome, is one of the most serious aquaculture diseases. A total of 150 Oreochromis niloticus, tilapia zilli, and clarias gariepinus with evidence of septicemia were randomly taken from El-Temsah Lake and fish farms in Ismailia governorate for isolation of P. aeruginosa and detection of its sensitivity to various antimicrobial drugs. The high rate of isolation was in Clarias gariepinus (42.5 %), Oreochromis niloticus (34.5 %), and then Tilapia zillii (26 %) were the most common fish species for P. aeruginosa. The highest prevalence was found in the liver (38.35 %), followed by kidney (30.58 %), spleen (19.9 %), and gills (11.17 %). According to antimicrobial resistance patterns, P. aeruginosa isolates were extremely resistant to Tetracycline and Oxytetracycline, Amoxicillin clavulanic acid, Ampicillin/ Sulbactam, Tobramycin, Cefotaxime, and Ceftriaxone, but very sensitive to Colistin (100 %). The isolated multidrug resistant P. aeruginosa should be followed up to control the disease in aquaculture industry.