The Donnet-Denhaut flying boat was a maritime patrol and anti-submarine warfare aircraft produced in France during the First World War. Known at the time simply as "Donnet-Denhaut" or "DD" flying boats, the DD-2, DD-8, DD-9, and DD-10 designations were applied retrospectively to denote the various changes in configuration made during their service life.

Donnet was a French manufacturing company of the early twentieth century. Founded as Société des Établissements Donnet-Denhaut by Jérôme Donnet and François Denhaut at Neuilly-sur-Seine in 1914, the firm manufactured a highly successful line of patrol flying boats for the French Navy. The company became known simply as Donnet after designer Denhaut left it in 1919, but did not continue to build aircraft for long afterwards.