AbstractExtraction of the aerial parts of Rubus coriifolius, a medicinal plant used by the Maya communities in Southern Mexico to treat bloody diarrhoea, resulted in the isolation of seven known compounds (−)‐epicatechin, (+)‐catechin, hyperin, nigaichigoside F1, β‐sitosterol 3‐O‐β‐d‐glucopyranoside, gallic acid and ellagic acid. All compounds were tested for their antiprotozoal activity against Entamoeba histolytica and Giardia lambia. Epicatechin was the main responsible for the antiprotozoal activity of the extract against both protozoa, its activity was comparable to emetine, but no exceeded that of metronidazole. Copyright © 2003 John Wiley & Sons, Ltd.