The aerial part of Equisetum telmateia Ehrh. is used against various conditions including stomachache and peptic ulcer in Turkish folk medicine. In order to prove the claimed anti-ulcerogenic potential of the plant, aqueous and methanol extracts were prepared from aerial parts of E. telmateia and investigated for their anti-ulcerogenic effect on ethanol-induced gastric ulcer model in rats. Pharmacological experiments clearly demonstrated that the oral administration of both methanol and aqueous extracts of Equisetum telmateia Ehrh. plant showed significant stomach protection (77.9% and 100% ulcer inhibition, respectively) against the applied model of ulcerogenesis (P < 0.001). Since both extracts were found significantly active, 80% ethanol was preferred for the extraction of the plant material and this crude methanolic extract was further fractionated by successive solvent extractions with chloroform and H2O saturated n-BuOH to obtain the chloroform and n-BuOH extracts as well as the remaining aqueous extract. The 80% ethanol extract and the solvent extracts were then submitted to pharmacological assay using the same in vivo experimental ulcer model. All the extracts statistically showed potent anti-ulcerogenic effect on this model (P < 0.001). However, the remaining aqueous extract was found prominent (98.2% ulcer inhibition). Consequently. folkloric utilization of E. telmateia on peptic ulcer has been confirmed in the present study by using ethanol-induced experimental ulcer model in rats.