The bacaba (Oenocarpus bacaba Mart.) is a palm that occurs in the Amazon Forest. The stem witich reaches seven to 22m in heig and diameter of 12 to 25cm, supplies excellent palm cabbage. The fruit is very delicious and used for wine, juices and ice-cream production. It is also used to made a homr-made cough medicine. Comestible oil similar to olive-oil is extracted from its pulp and seeds. To describe the morphology of this species, two hundred mature fruits, were collected, put in water at 50oC for 30 minutes. The pulp and all the residue were then removed. The diameter and length of the seeds were measured, as were their dry and wet weights. The other seeds were used for morphological observations. The seed is covered by a thin rust-colored, associated with the fibrous endocarp. It presents only one germinative pore. The endosperm is formed of dense tissue, with na oil reserve. The embryo has an irregular form, one extremity globular, containing to the cotiledon, the other cylindric, containing to the cotiledon peciole, where the embrionic axis is inserted.