Presence of Helicobacter pylori is associated with an increased risk of developing upper gastrointestinal tract diseases. Antibiotic therapy and a combination of two or three drugs have been widely used to eradicate H. pylori infections. Due to antibiotic resistant drugs, new drug resources are needed such as plants which contain antibacterial compounds. The aim of this study was to investigate the ability of GutGard$^{TM}$ to inhibit H. pylori growth both in Mongolian gerbils and C57BL/6 mouse models. Male Mongolian gerbils were infected with the bacteria by intragastric inoculation ($2{ imes}10^9$ CFU/gerbil) 3 times over 5 days and then orally treated once daily 6 times/week for 8 weeks with 15, 30 and 60 mg/kg GutGard$^{TM}$. After the final administration, biopsy samples of the gastric mucosa were assayed for bacterial identification via urease, catalase and ELISA assays as well as immunohistochemistry (IHC). In the Mongolian gerbil model, IHC and ELISA assays revealed that GutGard$^{TM}$ inhibited H. pylori colonization in gastric mucosa in a dose dependent manner. The anti-H. pylori effects of GutGard$^{TM}$ in H. pylori-infected C57BL/6 mice were also examined. We found that treatment with 25 mg/kg GutGard$^{TM}$ significantly reduced H. pylori colonization in mice gastric mucosa. Our results suggest that GutGard$^{TM}$ may be useful as an agent to prevent H. pylori infection.