The anti-ulcer activity of aqueous extract of Aegle marmelos leaves was investigated on a indomethacin induced ulcer models in wistar rats. In model the common parameter determined was ulcer-index. aqueous extract of dosage 175, 350 mg/kg p.o produced significant inhibition of gastric lesions induced by indomethacin induced ulcers. The extract 175mg/kg & 350mg/kg showed significant (p<0.01) reduction in gastric volume, free acidity and ulcer index as compared to control. This present study indicate that Aegle marmelos leaves extract have potential anti ulcer activity. This results may further suggests that aqueous extract was found to posses antiulcerogenic as well as ulcer healing property,which might be anti secretory activity. Key words: anti-ulcer,aegle marmelos, antisecretory ,indomethacin