Abstract : Despite the advent of various antimicrobials, nowadays, the community acquired and health care associated infections are relatively frequent with Proteus species. Its resistance to various groups of antibiotic has been increasing, which needs a continuous survey for better therapeutic response. From total 5055 samples, 591 (11.7%) Proteus mirabilis isolates were obtained. 186 (5.4%) from urine samples, 120 (18.5%) from wound 105 (30.7%) from blood, 172 (28.5%) from pus were isolated. Out 591 samples of Proteus mirabilis 185 (31.3%) were ESBL positive. Maximum samples were obtained from wound (37.5%), followed by pus (36.0%), urine (31.7%), and blood (16%). Statistical analysis was done using chi – square test and p value was found to be significant. The frequency of ESBL producing strains in our study was 31.3 %. In the present study, presence of ESBLs was determined with CLSI phenotypic confirmatory test (PCT), double disc diffusion test (DDST) and E-test. PCT detected 185 (31.3%) isolates, DDST detected 169 (28.5%) isolates and E - test detected 185 (31.3%) isolates. Thus a higher rate of ESBL detection was found with CLSI phenotypic confirmatory test. All the positive isolates detected in PCT were confirmed by MIC using E-test. The clinical laboratory standards institute (CLSI) also recommends the use of the combination disc method for the phenotypic confirmation of ESBL production among Enterobacteriaceae. The raising resistance to various groups of antibiotics is a common problem and its management is a subject of concern. Identification, surveillance and study of the epidemiology of antimicrobial resistance will assist in the therapeutic management of patients by reducing the prescription of large spectrum antibiotics control of infections. This study is therefore a step towards the generation of national data on the prevalence of antimicrobial resistance pathogens.