| Erdmann August of Brandenburg-Bayreuth | |
| Hereditary Prince of Brandenburg-Bayreuth | |
| House: | House of Hohenzollern |
| Father: | Christian, Margrave of Brandenburg-Bayreuth |
| Mother: | Marie of Prussia |
| Spouse: | Sophie of Brandenburg-Ansbach |
| Issue: | Christian Ernst, Margrave of Brandenburg-Bayreuth |
| Birth Place: | Bayreuth |
| Death Place: | Hof |
Erdmann August, Hereditary Prince of Brandenburg-Bayreuth (b. Bayreuth, 8 October 1615 – d. Hof, 6 February 1651), was a member of the House of Hohenzollern and Hereditary prince (German: Erbprinz) of Brandenburg-Bayreuth.
He was the seventh of the nine children of Christian, Margrave of Brandenburg-Bayreuth by his wife, Marie of Prussia. In fact, he was the third-born son but the only one to survive into adulthood; his two older brothers Georg Frederick (b. and d. 1608) and Christian Ernst (b. 1613 – d. 1614) died long before his own birth.
In Ansbach on 8 December 1641, Erdmann August married the Margravine Sophie of Brandenburg-Ansbach, who was also his first cousin (daughter of Joachim Ernst, Margrave of Brandenburg-Ansbach, his father's brother). They had only one son:
Sophie died on 3 December 1646. Erdmann August himself died four years later, aged thirty-five, in the middle of the preparations of his wedding with Sophie Agnes of Mecklenburg-Schwerin. Because he predeceased his father, his son Christian Ernst succeeded as Margrave of Brandenburg-Bayreuth in 1655.