BACKGROUND/AIMS: In recent years, increasing antimicrobial resistance has resulted in falling eradication rates with standard therapies. To overcome the falling eradication rates, rescue therapy have been suggested to be used. However, there is no surveillance of using bismuth-based regimen as first line Helicobacter pylori eradication therapy in Korea. This study aimed to assess the efficacy of bismuth containing PPI-based quadruple therapy as a first line treatment. METHODS: From August 2007 through February 2008, 191 patients with Helicobacter pylori positive peptic ulcer disease (PUD) or chronic gastritis (CG) who received first line therapy for 7 days were retrospectively evaluated. 39, 37, 53, 62 patients received PAC (pantoprazole 40 mg, amoxicillin 1 g, clarithromycin 500 mg bid), L-PAC (pantoprazole 40 mg, amoxicillin 750 mg, clarithromycin 250 mg bid), PACB (PAC plus bismuth 300 mg bid), L-PACB (L-PAC plus bismuth 300 mg bid). RESULTS: There was no significant difference in eradication rates between bismuth containing and non- containing group. However, in PUD, the eradication rate of PACB (95.2%) is somewhat higher than that of PAC (86.2%) without statistical significance. CONCLUSIONS: In PUD, Future study designed with a double-blind controlled large scale might reveal that PPI-based standard quadruple therapy containing a bismuth is superior to the standard triple therapy.