Gonystylus othmanii grows as a tree up to 10 metres (33 ft) tall, with a trunk diameter of up to 20 centimetres (10 in). The bark is greyish brown. The fruit is brown, up to 5.5 centimetres (2.2 in) long. Its habitat is lowland mixed dipterocarp forest. G. othmanii is endemic to Borneo where it is known only from Sarawak.