Indomethacin induced ulcers in wistar rats was the main model of investigation of the anti-ulcer activity of the ethanolic extract of Cissampelos pareira Linn Pennel leaves in which ulcer index was used as the primary parameter. Inhibition of gastric lesions of the ethanolic extract of the leaves was observed at doses of 175mg/kg and 350 mg/kg when taken orally. At these doses, notable reduction in the gastric volume, free acidity and the ulcer index were observed when compared to the control group. From the results obtained, it can be noted that the ethanolic extract of Cissampelos pareira Linn Pennel leaves have anti-ulcer activity which can also be called as anti-secretory activity. Key Words: Cissampelos pareira Linn Pennel, anti-ulcer activity, ulcer index, Indomethacin