The choice of antibiotics used for first line treatment of infectious disease depends largely on previously known antibiogram within a specified locality among other factors. Antibiotic sensitivity pattern of Pseudomonas aeruginosa isolates obtain from clinical specimen in Ilorin, Nigeria was studied over a 12 month period, starting from January 2003. A total of 102 isolates were recovered from various clinical specimens and their antibiotic sensitivity patterns were determined by disc diffusion method on antibiotic sensitivity agar (ASA). Single antibiotic discs (AD) were used. The isolates were incubated at 37 degrees C for 18-24 hours following inoculation on ASA and application of AD before the results were read. Most isolates were sensitive to ofloxacin (77.6%), cefuroxime (76.6%), ciprofloxacin (75.3%), perfloxacin (66.0%), streptomycin (64.0%) and gentamicin (59.8%). Appreciable resistance to ceftazidime (50.7%) and increasing resistance to gentamicin (40.2%) than is previously known, were recorded. Urinary isolates were generally more resistant than isolates from other sources. Majority of the isolates were recovered from patients attending the general out-patient department of the hospital indicating extension of multi-drug resistant microbial isolates beyond hospital settings. Review of antibiotic sensitivity pattern of clinical isolates regularly and the antibiotics prescribing policy in the country is advocated. Combination of quinolones and aminoglycosides, where these are no contraindications, is recommended for first line treatment of suspected cases of Pseudomonas aeruginosa infections because of non-availability of anti-pseudomonad drugs in the country.