Prince August of Saxe-Gotha-Altenburg (14 August 1747, in Gotha – 28 September 1806, in Gotha) was a German prince of the Saxe-Gotha-Altenburg line of the Ernestine Wettins and a patron of the arts during the Age of Enlightenment.

He was the youngest child of Frederick III, Duke of Saxe-Gotha-Altenburg and his wife Princess Luise Dorothea of Saxe-Meiningen.

Their mother made sure both August and his brother Ernest received a good education in literature, science and cameralism.

August's parents had planned a military career for him, but he gave this up in 1769, handing over his Gotha infantry regiment in 's-Hertogenbosch to his nephew Frederick.

Considered to be an enlightened, open-minded and progressive prince, he gathered a witty circle around him at his palace in Gotha from 1778 onwards.