Aim: Pseudomonas aeruginosa is a classic opportunistic pathogen with innate resistance to many antibiotics and disinfectants. It is ubiquitous in hospital environment and because of its ability to survive in hospital environment it creates threat to patient’s care.The antibacterial effect of acetic acid against multiple antibiotic resistant strains of Pseudomonas aeruginosa isolated from nosocomial wound infection cases was studied. Methods: For this study, seven hospitalized patients with wound infections, not responding to traditional therapy for more than 10 days, were selected. A specimen of pus was collected before application of acetic acid and after completion of treatment (only one reculture was done) and processed for culture study. Seven clinical isolates of P. aeruginosa were studied for in vitro susceptibility to acetic acid and all were found to be inhibited by 3 % acetic acid. Results: The pus culture yielded isolation of P. aeruginosa in all seven cases under study. No other bacterium was isolated from these cases; hence they were labeled as pseudomonal wound infections. All isolates were found to be resistant to four or more antibacterial agents but all of them were found to be inhibited by 3% acetic acid in vitro when exposed for 15 minutes or more. Topical application of 3 to 5% acetic acid to wounds for 2 to 12 times successfully eliminated P. aeruginosa from wounds. Conclusion: The use of acetic acid is therefore recommended for effective elimination of multiple antibiotic resistant strains of P. aeruginosa from infection site.