A series of five 5-(aryloxy)-4-methylprimaquine analogues has been prepared and evaluated for antimalarial activity. The compounds were tested for suppressive activity against Plasmodium berghei in mice and for radical curative activity against Plasmodium cynomolgi in the rhesus monkey. The compounds were not only significantly superior to primaquine as radical curative agents but also were suprisingly highly effective as suppressive agents.