The aim of this study was evaluate methods to overcome seed dormancy, and to stablish substrate and temperature for germination test of Acacia mangium seeds. The following methods were used to overcome dormancy: immersion in water at 40°C temperature for 24 hours; immersion in water at 80°C temperature, taking the seeds out of water after attained environmental temperature (2 hours); immersion in 96% H2SO4 for 30 minutes and immersion in 20% NaOH for one hour. The substrates evaluated were: sand; roll of paper towel and on filter paper, placed inside the germinator at 25 and 35°C constant temperature and 25-35°C alternated, during 21 days. The parameters evaluated were: percentage and length of normal seedlings at 7 and 21 days after seeding. The results showed that: a) the immersion of seeds in water at 80°C temperature, was the best method to overcome seed dormancy of Acacia mangium. b) the substrate roll of paper towel (RP) and 35°C constant temperature should be used to conduct germination test of Acacia mangium seeds.