Peptic ulcers are a comprehensive term that includes ulcers of digestive tract in the stomach or duodenum. The formation of peptic ulcers depends on the presence of acid and peptic activity in gastric juices and breakdown in mucosal layers. A number of synthetic drugs are available to treat ulcers. But these drugs are expensive and are likely to produce more side effects when compared with the herbal medicines. The literature revealed that many medicinal plants and poly herbal formulations are used for the treatment of ulcers in gastro intestinal tract .One of the Poly herbal preparation was Saaranaiver chooranam mentioned in the Siddha literature the solitary ingredient, root of Trianthema decandra Linn., (Vellai saaranai-Punarnavi) which possess an anti-ulcerogenic activity. The present study was performed in pylorus ligation induced ulcer model in Wister rats, in which ability to provide gastric protection was studied at two different doses 200 and 400 mg/kg calculated based on the acute toxicity study. Gastric protection was evaluated by assessing various parameters like gastric volume, pH, total acidity, free acidity, ulcer index and percentage inhibition of ulceration. Ranitidine at 50 mg/kg was used as the standard drug. The test drug, Saaraanaiver chooranam (especially at 200mg/kg dose) was found to be equally efficacious with the reference drug, ranitidine (50mg/kg showed significant (P<0.001) decrease in the gastric volume, total acidity and free acidity. However, pH of the gastric juice significantly (P<0.001) increased at the dose, 400 mg/kg. It also showed a significant (P<0.001) decrease in number of ulcers and ulcer score index. In conclusion the anti-ulcer activity is evident from its significant reduction in degree of ulceration. Hence the study represents Saaraanaiver chooranam (Trianthema decandra Linn) has good anti-ulcer activity.