Ibicella lutea (Lindl.) Van Eselt. (Martyniaceae) is the sole species of the genus Ibicella from the small Martyniaceae family comprising just 3 genera (Martynia, Proboscidea and Ibicella) with 13 species. In Uruguay, where the plant grows freely, it is called “cuerno del diablo” (Devil’s horn) and its infusion is used in popular medicine as an antimicrobial for the treatment of eyes and skin infections. In this work we present the antibacterial activity of two compounds isolated from I. lutea against several S. aureus strains, both sensible and resistant. Both compounds were active against at least some of the S. aureus strains tested with MICs from 32 to 125 μg/mL, and further studies are being performed.