Campomanesia xanthocarpa O. Berg., popularly known as "gabiroba", is used in Brazilian folk medicine for ulcer treatment. The hydroalcoholic extract of Campomanesia xanthocarpa leaves was evaluated for antiulcerogenic activity, acute toxicity and phytochemical profile. Oral administration of the extract at 400 mg/kg proved to be effective in preventing gastric ulceration in rats and did not produce toxic symptoms in mice in doses up to 5 g/kg. TLC screening methods revealed the presence of flavonoids, saponins and tannins.