Peptic ulcers, a prevalent gastrointestinal disorder, necessitate effective treatment options to mitigate symptoms and promote healing. Lupinus arboreus, a plant known for its various medicinal properties, was evaluated for its potential to prevent and heal gastric ulcers. This study investigated the pharmacological evaluation of the anti-ulcer activity of methanolic leaf extract of Lupinus arboreus on Wistar rats, along with a comprehensive phytochemical analysis of the plant. The study employed a methanol extraction method to obtain the active constituents from the leaves of Lupinus arboreus. The phytochemical analysis revealed the presence of flavonoids, tannins, saponins, and alkaloids, which are known to contribute to gastro protective effects. The anti-ulcer potential was assessed using ulcer model induced by ethanol. Various dosages of the methanolic leaf extract were administered to evaluate their efficacy in reducing ulceration, compared to standard anti-ulcer drugs. Parameters such as ulcer index, gastric juice volume, pH, of the stomach lining were analyzed. The methanolic extract exhibited significant anti ulcer activity, evidenced by reduced ulcer index and enhanced mucus production. These findings suggest that Lupinus arboreus leaves possess potent anti-ulcer properties, likely due to its rich phytochemical profile.