One hundred ninety five Gram-negative bacilli (94 E. coli, 50 Klebsiella-enterobacter- Serratia group, 30 Pseudomonas spp, 16 Proteus spp and 5 other species) isolated as urinary pathogens were tested for their susceptibility to aminoglycoside antibiotics. The results were evaluated by comparing the MIC values by the breakpoints of the antimicrobial agents. Amikacin were found as the most effective antimicrobial of the group, 94.7 % of bacteria were susceptible to amikacin. The susceptibility to other antimicrobials were ranked as follows: netilmicin (83.6 %). tobramycin (72.1 %). gentamicin (71.0 %) and kanamycin (23.6 %). Significant differences were recorded among the distribution of the bacteria coming from in-patients and out-patients, and among the bacteria corfling from different departments (p < 0.05). Among the groups of bacteria the Pseudomonas species were the most resistant group and the majority of them were isolated from Urology patients. We concluded that most of the aminoglycoside antimicrobials are still very effective on E.coli strains, while amikacin is very effective for most of the bacteria, including Pseudomonas and Proteus species which are rather hard to eradicate.