Objective To discuss and establish a method for screening of the metallo ? lactamase in the clinical microbiology laboratory in order to help choosing antibiotics. Methods The enzyme inhibitor was EDTA.K 2, and the substrate were ceftazidime, cefotaxime. and imipenem. The microbiology sensitivity synergic tests, were processed by KB method in the M H agar. and compared with the PCR results of metallo beta lactamase gene detection. Results The metallo ? lactamase producing bacteria, synergize with EDTA K2 disc at least in one of the three kinds of substrate In 132 of imipenem resistance strains, the metallo ? lactamase positive strains were detected by this method was 88 and that by PCR was 63, respectively. 61 strains were positive detected by the two methods synchronously, as well as 44 strains were negative, 2 strains were positive detected by PCR assay but negative by this method, and, 27 strains were contrary. Conclusion This method was simple, credible and cheap. It was suitable for screening detection of the metallo ? lactamase routinely in the clinical microbiology laboratory.