The Dornier Do J was a German flying boat designed in the 1920s by Dornier Flugzeugwerke. It was primarily used for maritime reconnaissance and passenger transport. The aircraft featured a distinctive high-wing design and was powered by two engines mounted on the wings, allowing for improved stability and performance over water. First flown in 1926, the Do J had a capacity for up to ten passengers and was notable for its spacious cabin. Its design was influenced by earlier models, such as the Dornier Wal, and it played a role in the development of future flying boats in the aviation industry.