Nitroimidazoles, including metronidazole and tinidazole, have been used in multiple antimicrobial therapy strategies to eradicate Helicobacterpylori in peptic ulcer patients and nonulcer dyspeptic patients (1, 19). However, emergence of primary resistance and acquired resistance to these kind of drugs in H. pyloni may lead to treatment failure (3,7,10,11,21,27). Thus, evaluation of H. pylotn susceptibility to metronidazole before treatment appears to be important. Metronidazole resistance rates from 6.4 to 84% have been reported throughout the world (2,11,13,22