BACKGROUND: Helicobacter pylori(H. pylori) is an important etiologic agent for chronic active gastritis and plays a role in the pathogenesis of peptic ulcer and stomach cancer and recently lymphomas occurring in mucosa associated lymphatic tissue. At present, H. pylori infection associated gastritis was estimated about 80% among the cause of chronic gastritis. In this study, we tested Polymerase Chain Reaction (PCR) assay to detect H. pylori infection in gastric biopsy specimens. This results were compared with results obtained by other tests. METHODS: A total of 70 patients with dyspepsia were evaluated for H. pylori infection through the use of PCR, culture and serologic tests. The study population had an age of 12 to 80 years(median 46.4), there were 31 males and 39 females. We tested PCR using H. pylori detection kit(TM) (Bioneer, Korea) and anti-H. pylori anti-body EIA using GAP test IgG and IgM(TM)(BIO-RAD, USA). We used anaerobic jar without catalyst for the microaerophilic condition. RESULTS: The positive result by PCR assay for diagnosis of H. pylori infection in gastric specimens was 71.4% in total of 70 patients, which the gastritis, peptic ulcer and gastric cancer were 63.2%, 77.8% and 85.7%, respectively. Among 10 gastrectomy specimens of stomach cancers, the detection rate of H. pylori infection by culture was 50% and the PCR assay was 100%. The detection rate of If pylori IgG and IgM antibodies by commercially available GAP test IgG and IgM EIA were 64.3%, respectively, and IgG or IgM were 85.7%. CONCLUSIONS: The serologic study was sensitive but it was appeared that the high false positive (75%) and false negative (25%) rate and could not confirm current infection. The PCR assay was shown to be more sensitive, rapid and easy to treat specimen for the detection of H. pylori infection than conventional methods such as culture and serologic test in dyspeptic patients.