We investigated the eradication rate and the adverse effects of combined treatment with western and oriental medication on Helicobacter pylori infected patients. We studied the eradication rate and the adverse effects of 1-week-triple therapy and 2-week-oriental medication(Banhasasimtang or Hyangsapeungeuysan) on Helicobacter pylori infected patients confirmed by urea breath test. Comparing 5 patients who took combined treatment with western and oriental medication, the results of this study showed that 4 patients got eradication effect of Helicobacter pylori with no influence on liver and kidney function. A patient had diarrhea and another patient had satiety after meals because of an adverse effect. Despite some possitive effect, the treatment did not make the Quality of Life improved. The findings of this study supports the adverse effects of combined treatment with western and oriental medication for the treatment of Helicobacter pylori infection.