| August | |
|---|---|
| Duke of Schleswig-Holstein-Sonderburg-Beck | |
| Predecessor | August Philipp |
| Successor | Frederick William I |
| Born | 13 February 1652 |
| Died | 26 September 1689 (aged 37) near Bonn, Archbishopric-Electorate of Cologne |
| Spouse | Hedwig Louise of Lippe-Alverdissen |
| House | House of Oldenburg |
| Father | August Philipp, Duke of Schleswig-Holstein-Sonderburg-Beck |
| Mother | Marie Sibylle of Nassau-Saarbrücken |
August, Duke of Schleswig-Holstein-Sonderburg-Beck (13 February 1652 – 26 September 1689) was a Danish nobleman. From 1675 until his death, he was the ruling Duke of Schleswig-Holstein-Sonderburg-Beck. He was the second duke of this appanage.