Resumo. Anadenanthera macrocarpa (Benth.) Brenan is a tree species belonging to the family Leguminosae- Mimosoideae which is popularly known as mimosa-black. It features characteristics of early successional, natural occurrence in Brazil and can form clusters almost homogeneous, with great potentialin the recovery of degraded areas. This study was conducted at the Center for Agricultural Sciences,University Federal of Alagoas state, aiming at the physical and morphological characterization of seeds, describing the various stages of post-seminal development, and to evaluate various conditions of temperature and substrate toperform the test germination. The seeds were manually extracted, then homogenized, where two samplesof 50 seeds were used to determine the initial moisture. Another sample, consisting of eightrepetitions of 100 seeds was used to measure the biometry and the number of seeds per fruit. Themorphological characterization and the seeds were immersed in distilled water to allow the cuts to the observed structure in microscopes. In the post-seminal study, it was observed the daily processes of seedling growth in rolledpaper filter and constant temperature of 30 °C. To assess the germination behavior,theconstant temperatures of 15 °C, 25 °C, 30 °C, 40 °C and 20-30 °C as well as the paper and the sand substrateswere tested and it was evaluated the percentage, the rate of germination, the relative frequencydistribution, and the testsconducted in a randomized design in factorial 5 x 2 (x substrate temperature) with four replicates of 25 seeds,and the averages compared by Duncan 5 % probability. The fruits of black angico show great variation in the seed number per fruit. The embryonic axis occupies part of the central region of the seed with axial andlinear positions. The germination is epigeal and the seedlings are fanerocotylar. The temperature determinesthe 30 °C and the filter paper substrate provided higher average percentage and germination rate.