Background & objectives : Helicobacter pylori is considered as an important factor in chronic gastritis , peptic and duodenal ulcer, also probably in adenocarcinoma of distal stomach. H. Pylori infection can be led to chronic ulcers and ultimately to atrophy and stomach metaplasia. H. pylori shows an increasing resistance to the current antibiotics. For this reason the present research in which the anti bacterial effects of four food additive plants against ten strains of H. Pylori were investigated.

  Methods : The plants turmeric, ginger, clove and cardamom were selected to act against ten strains of H. Pylori. The effect of ether, ethanol and water extracts on H. Pylori specimens isolated from the patients was studied, using the agar diffusion method .

 Results: Considered water extracts for their antibacterial effects, turmeric had the most anti H. Pylori efficacy (mean of inhibitory growth zone diameter 21.5 mm). Ginger, clove and cardamom were respectively placed thereafter. Among ethanol extracts, ginger with diameter mean of 19.7 mm showed the most efficient effect as compare with turmeric and clove. Ether extracts of the mentioned plants had anti H. Pylori effects (Mean of inhibitory growth zone diameter were 19, 13, 11.1 and 10.5 mm respectively

 Conclusions: Water, ethanol and ether extracts of turmeric had higher anti H. Pylori activity. Recognition of the effective fraction 0f this plant as an efficient anti H. Pylori is further step to be investigated.