The lesion of peptic ulcer disease (PUD) is a disrflption in the mucosal layer of the stomach orrnduodenum. An ulcer is di stinguished from erosion by its penetration through the muscularisrnmucosa or the muscular coating of the gastric or duodenal wall. PUD results from thernimbalance between defensive factors that protect the mucosa and offensive factors that disruptrnthis important barrier. There are several different types of modern drugs for the treatment ofrnPUD though they are associated with clinically significant drug interactions, side effects, andrnrelapse. Thus, there is a need to develop new drugs. for which natural products are potentialrncandidates. Planlago lanceolala is used traditionally for the treatment of upper respiratoryrninflammation, urinary conditions. uterotonic. vascular disorders. wound, cough, ulcer etc.rnThe present study was undertaken to evaluate the anti ulcer activity of the aqueous extract, andrnmucilage of P. lanceolala using different rodent models of PUD. Negative controls were givenrndistilled water. Whilst positive controls received ranitidine in acetic acid induced chronicrngastric ulcer, cysteamine Hel induced duodenal ulcer and pylorus ligation induced gastricrnulcer models; misoprostol was used in indomethacin induced gastric ulcer. One group ofrnanimals received 200 mg/kg (for mice) and the other group received 400 mg/kg (for mice) ofrnthe aqueous extract in each model. In addition, one group of animals received 172 mg/kg ofrnthe mucilage in acetic acid induced chronic gastric ulcer model.rnThe aqueous extract showed a better healing of ulcer than the mucilage in the acetic acidrninduced chronic gastric ulcer as evidenced by the higher percent reduction in ulcer indexrn(77.9% vs 51.9%) and ulcer score Crable I). The aqueous extract was therefore, used forrnfurther evaluation. The effect of the aqueous extract at 400 mg/kg was more effective inrnhealing and/ or protecting ulcer in virtually all models than 200 mg/kg.rnThe extract at both 200 mg/kg and 400 mg/kg produced reduction in ulcer index (P