Phytochemical re-examination of the aerial exudates of Polygonum senegalense forma senegalense has resulted in the isolation and characterization of a novel homoisoflavonoid, 5,7- dihydroxy-3-(hydroxy-phenyl-methyl)-6-methoxy-chroman-4-one (trivial name: polygohomoisoflavanone). The structure was determined on the basis of spectroscopic evidence. The new compound along with other components of the aerial exudate showed good antiplasmodial activities towards chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum.