August, Duke of Saxe-Merseburg-Zörbig (Merseburg, 15 February 1655 – Zörbig, 27 March 1715), was a German prince and member of the House of Wettin.
In order to provide his three younger sons with an income befitting their status, Duke Christian I, assigned to each of them before his death a small territory as appanage; however, these territories remained dependent on the senior Saxe-Merseburg line, and their sovereign powers were severely limited.
In consequence, August relocated his household from Alt-Stargard, which he had received from his father-in-law as a dowry, to Zörbig.
In particular, he continued the reconstruction measures started by his father in the region damaged by the Thirty Years' War.
In 1694 he ordered Castle Zörbig to be rebuilt into a new and comfortable residence; however, August died before the works were finished.