Pseudomonas aeruginosa isolates are well known cause of outbreaks of various nosocomial infection. These organism are difficult to treat as they exhibit varying degrees of innate and acquired resistance mechanism. This study was undertaken to analyse various acquired resistance mechanism like Extended spectrum - lactamase (ESBL), Metallo -lactamase (MBL) and inducible AmpC beta ( )- lactamase, enzymes in clinical isolates of Pseudomonas aeruginosa. The study included a total of 203 consecutive non-duplicate isolates of Pseudomonas aeruginosa obtained from clinical specimens like pus (103), urine (50) and sputum (50). Phenotypic detection of Extended spectrum beta-lactamase (ESBL), Metallo -lactamase (MBL) and AmpC beta-lactamase (AmpC -lactamase)of Pseudomonas aeruginosa were done by Phenotypic confirmatory disc diffusion test, Disk potentiation test and Disk antagonism test respectively. Of 203 isolates, 49(47.6%), 52(50.5%) and 21(20.4%) were Extended spectrum beta-lactamase( ESBL), Metallo -lactamase and AmpC -lactamase producers respectively..In conclusion, our study has shown high incidence of ESBL and MBL producing Pseudomonas aeruginosa. Multi-drug resistance were found to be 52 (25.6%) Henceforth, strict antibiotic policies and measures to limit the indiscriminative use of cephalosporins and carbapenems in the hospital environment should be undertaken to minimize the emergence of multiple -lactamase.