Аннотация:Jodina rhombifolia (Hook. & Arn.) Reissek (Santalaceae) is a medicinal plant popularly used as an anti-ulcer medicine. The plant native from Southern Brazil was chemically investigated and tested for its in vivo gastric anti-ulcer property by chloride acid/ethanol model. The chromatographic analysis of the hydroethanol extract of its leaves revealed the presence of C-glycosylflavonoids. From the n-butanol fraction of the hydroethanol extract of its aerial parts, vicenin-2 was isolated as the main component and identified by spectroscopic methods; and, a direct comparison with authentic samples was made. This fraction afforded three other C-glycosylflavonoids: vitexin, orientin and swertisin; all of them identified by direct comparison with authentic samples. We found that the oral administration of aqueous and hydroethanolic extracts led to a significant decrease in the ulcer index.