The essential oil from Adenocalymma alliaceum leaves (ca. 0.04%) was investigated with GC and GC-MS. Of the 13 compounds tentatively identified, 9 are likely to be part of a homologous series. The most abundant components were diallyl disulfide and diallyl trisulfide, which comprise 62% of the oil. The garlic bush (Portuguese, cipó d'alho) is a widespread plant in Brazil, particularly in the north where the principal species is Adenocalymma alliaceum Miers. Upon the sample handling of the large leaves, a strong odor exudes, similar to that of garlic (Allium sativum). Although infusions of the leaves are used in treating colds and fevers (Pio Correa, 1931; Figueiredo, 1979), its principal use is in the substitution of garlic, especially in the interior regions of difficult access. The ethereal extracts of steam distillates from fresh leaves of the garlic bush were first studied by Apparao et al. (1978), using packed column gas chromatography-mass spectrometry (GC-MS). The principal components of the extracts to be the diallyl di-, tri-, and tetrasulfides. Not surprisingly, these are also among the major constituents in garlic (Oaks et al., 1964; Brodnitz et al., 1971). As part of an ongoing study of the essential oil of amazonian plants, we have characterized the volatiles of garlic bush, using capillary column gas chromatography-mass spectrometry, and we now report the presence of additional alkenyl sulfides.