Abstract: Spontaneous point mutations are considered as major antibiotic resistance mechanism for Helicobacter pylori. Anti-mutagenic properties of some medicinal plants are evaluated in the present study. This could be a novel attractive approach in reducing the resistance phenomenon in H. pylori. The mutation prohibiting properties of ethanolic extract from Cuminum cyminum, Mentha piperita and Camellia sinensis were assayed by comparing mutation frequency for clarithromycin resistance in three H. pylori clinical isolates in the absence and in the presence of plant extracts. A-to-G transition at 2143 position of 23S rRNA gene was demonstrated as only point mutation in the all resistant mutated colonies. Furthermore, the median mutation frequency to clarithromycin resistance was detected as 27x10-9 for three isolates which was reduced after application of M. piperita, C. cyminum and C. sinensis extracts by 55.5, 68.5 and 99.5%, respectively. In the base of the results C. sinensis as a widely consumed beverage may be considered as potential sources of these agents.