ABSTRACTUlcer can get developed inside the inner lining of the stomach (gastric ulcer) or the small intestine (duodenal ulcer). Both the ulcers are also cumulatively referred as peptic ulcers. This Prenanthes Sarmentosus leaves were used for reducing gastric irritation by people. This study was performed to avoid folklore belief.  The present study was carried by pylorus ligation, aqueous alcohol induced ulcer models in albino rats. The antiulcer activity of AAPS (150, 300 mg/kg p.o. for 10 days) was compared with standard drug (Omeprazole 0.5 mg/kg body weight). In pyloric ligation induced ulcer model, the studied parameters were gastric volume, pH, total acidity, free acidity, and ulcer index were determined for observing the severity of ulcers. In this study the volume of gastric content, total/free acidity was significantly decreased at p