This tree can grow 10 to 20 metres tall. Its cylindrical trunk is often swollen at the base. This characteristic feature of the Bombacoideae subfamily allows it to store water reserves during periods of drought.
Its leaves are palmately compound and evergreen, made up of 5 to 9 large leaflets that can reach 30 centimetres in length.
The flowers, usually solitary, have 5 large white, green, or yellow petals measuring up to 35 centimetres. Their stamens are notable for both their length and their number, ranging from 200 to 360. Near the tips, they are violet in colour, with reddish anthers, where the pollen is produced. The stamen filaments are fused at the base, forming a tube around the pistil. The flower is fragrant.
The fruit of the Guiana chestnut is a brown, woody capsule shaped like an elongated ball and measuring 15 to 30 centimetres. It can contain up to about 20 large, angular seeds, 3 to 4 centimetres long, surrounded by cottony fibre.