The Army of the Danube () was a field army of the French Directory in the 1799 southwestern campaign in the Upper Danube valley. It was formed on 2 March 1799 by the simple expedient of renaming the Army of Observation, which had been observing Austrian movements on the border between First French Republic and the Holy Roman Empire. It was commanded by General Jean-Baptiste Jourdan, 1st Comte Jourdan (1762–1833).