The amphibious AG600 is about the size of a Boeing 737 and will be used to fight forest fires and perform marine rescue operations, state-run news agency Xinhua said.
The spruce goose made by Howard Hughes was a larger seaplane. It weighed 180 tons and had a 97 meter wingspan.
With a maximum take-off weight of 53.5 tons, the AG600 is the largest seaplane in the world, Xinhua said. It has a reported flight range of 4,500 kilometers and can collect 12 tons of water in only 20 seconds.
China has had the 45 ton Harbin SH5 seaplane. The new seaplane is 22% bigger.
The AVIC General Aircraft Company has won 17 orders for the amphibious aircraft AG600, including two at 2014 Zhuhai Air Show.
AVIC expected to deliver 60 AG600 amphibious aircraft in 15 years. The AVIC TA-600, also known as AG-600, is a large amphibious flying boat that is being designed and built in China by the Aviation Industry Corporation of China (AVIC).