Introduction: Metallo-β-lactamase (MBL) produsing Pseudomonas aeruginosa has emerged as a threat to hospital infection control, due to its multi-drug resistance. Nowadays treatment of this infection is a serious problem due to spreading of antibiotic resistance. In this study, the frequency of blaVIM (1,2) , blaIMP(1,2) genes in P.aeruginosa strains isolated from samples of of health centers in Khorasan Razavi province was investigation by phenotypic and genotypic methods. Materials and Methods: Totally 74samples of P.aeruginosa were collected from Khorasan Razavi\\\'s hospitals during the years of 2017-18 and identified by biochemical methods. In these strains, the production of Metallo-β-lactamase was measured by Combined disk method and the presence of blaVIM (1,2) , blaIMP(1,2) gene was investigated by multiplex PCR method. Results: The highest rate of infection is related to urinary culture (45.94%). Totally, 38 samples (51.35%) were diagnosed as MBL by Combined disk method. in Multiplex PCR 11 samples (14.8%) contained blaVIM1 gene, 3 samples (4%) contained blaVIM2 genes. 12 samples (16.2%) contained blaIMP2 genes and None of the strains contain the blaIMP1 gene. Conclusion:The blaVIM1 and blaIMP1 gene has the highest frequency among the samples and The highest rate of infection is related to the urine specimen. Considering the increasing of antibiotic resistance, identifying the type of resistance and selecting the appropriate drug can be a major step in the treatment and control of infections caused by this bacteria.

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