Portrait of Forster by J. H. W. Tischbein

Johann Georg Adam Forster (November 26, 1754 - January 10, 1794) was a German botanical collector and artist.

He was born in Nassenhuben near Danzig (Gdańsk) in the Polish province of Royal Prussia, the son of Johann Reinhold Forster. With his father he took part in James Cook's second expedition to the Pacific (1772-75), on board HMS Resolution. On his return he published an account of the voyage entitled A Voyage round the World in His Britannic Majesty's Sloop Resolution, Commanded by Capt. James Cook, during the Years, 1772, 3, 4, and 5 (1777).

As a child his father had already taken him along on travels and both Forsters published travel descriptions to the South Sea in the Magazin von merkwürdigen neuen Reisebeschreibungen ("Magazine of notable new travel accounts") in Berlin, Georg Forster a translation of A Voyage to the South Sea, by Lieutenant William Bligh, London 1792 in 1791 and 1793. The descriptions of those travels were the basis for many books and films of the Mutiny on the Bounty.

Forster became Professor of Natural History at Vilnius on his return to the continent, and made a tour of the Rhine with Alexander von Humboldt. However, he expressed support for the French Revolution and was exiled from Germany as a traitor. He died in Paris.