The volatile constituents of the fruits of Annona glabra L. growing wild in North Brazil were analysed by GC–MS. The fruits were collected at three stages of ripening: unripe, half-ripe and ripe. The most abundant class of compounds found in the aromas were terpenoids. The major components identified were α-pinene (unripe, 18.5%; half-ripe, 11.3%; ripe, 15.0%), limonene (unripe, 20.0%; half-ripe, 20.7%; ripe, 20.6%), α-phellandrene (unripe, 21.0%; half-ripe, 1.2%; ripe, 2.0%) and (E)-β-ocimene (unripe, 15.8%; half-ripe, 19.7%; ripe, 18.3%). © 1998 John Wiley & Sons, Ltd.