Bioactivity-guided fractionation of extracts of roots and leaves of Cajanus cajan afforded 8 compounds: betulinic acid, biochanin A, cajanol, genistein and 2′-hydroxygenistein, longistylin A and C, and pinostrobin. The two stilbenes, longistylin A and C, and betulinic acid showed a moderately high in vitro activity against the chloroquine-sensitive Plasmodium falciparum strain 3D7.