Infection with Helicobacter pylori leads to gastritis, peptic ulcers and gastric cancer. Moreover, when the gastric mucosa is exposed to H. pylori, gastric mucosal inflammatory cytokine interleukin-8 (IL-8) and reactive oxygen (ROS) species increase. Tribulus terrestris L. is an annual creeping herb of the family Zygophyllaceae. In this study, the effect of Tribulus terrestris L. fruits extract (TTE) extract on H. pylori-infected human gastric epithelial cells was examined. Cell viability was determined by the tetrazolium salt reduction method using WST-1 according to the manufacturer's instructions. AGS cells were pretreated with TTE extract for 24 hrs followed by H. pylori infection for up to 24 hrs. IL-8 secretion in AGS cells was measured by ELISA. The extract yield of the fruits of Tribulus terrestris with 50% ethanol was 20.60%. We analyzed TFE composition by LC. The concentration of Protodioscin in TFE was 310 µg/mL. It was confirmed that exposure to 100 µg/mL of TTE had no significant effect on cell proliferation at the concentrations examined (12.5??00 µg/mL). It was therefore concluded that TTE at these concentrations had no cytotoxic effects on AGS cells and could be used in this study. Pretreatment of H. pylori-infected AGS cells with 12.5, 25, 50 and 100 µg/mL of TTE for 24 hrs significantly decreased IL-8 production by 12.5%, 25%, 27.5% and 50%, respectively, compared to H. pylori-infected cells without TTE. In this study, we found that TTE inhibited H. pylori-induced IL-8 secretion, thus augmenting their benefit in regard to protection of gastric epithelial cells. This study suggests that ingestion of these plant extracts could have therapeutic implications for patients with H. pylori induced gastritis and duodenal ulcer.