The contents of the main components of the primary metabolism (soluble sugars, starch, proteins, oils, fatty acids) and minerals (P, Ca, Mg, K, Fe, Zn, Mn, Cu) were characterized in seeds of five Brazilian Amazon tree species (Andira parviflora, Bertholletia excelsa, Helicostylis tomentosa, Hymenaea parviflora, and Parkia pendula). Soluble sugar contents were high in P. pendula seeds (14 %), whereas starch predominated in A. parviflora seeds (58.7 %). A. parviflora and H. parviflora seeds were rich in proteins (35.1 % and 32.4 %, respectively). The oil contents ranged from 1.4 % in A. parviflora to 70.7 % in B. excelsa. Only B. excelsa and P. pendula seeds may be considered oilseeds, with 70.7 % and 28.4 % oil, respectively. The fatty acid compositions showed high proportions of unsaturated fatty acids, mainly oleic and linoleic acids, regardless of the species. B. excelsa and P. pendula also showed high amounts of P, Mg, K and Zn.