The structure features a gently undulating roof, with external walls constructed from lengths of cedar wood.
Supporting rods allow the building to look from a distance as though it is suspended in the air.
Organisers said it was intended to look like a "a wooden bowl, floating in the bay area".
The building, one of a handful custom-built for the Games, "symbolises Japan's wood culture and viewers can feel its simple beauty", the organisers said.
"We're using a lot of wood," venue general manager Koichi Fukui told reporters. "We can smell wood and feel the warmth of wood," he said. Built at a cost of 20.5 billion yen, the venue features a domed ceiling constructed from Japanese larch with no steel framework and is among the largest of its kind in the world.