| Agnes of Hesse-Kassel | |
| Princess of Anhalt-Dessau | |
| House: | House of Hesse |
| Father: | Maurice, Landgrave of Hesse-Kassel |
| Mother: | Juliane of Nassau-Siegen |
| Spouse: | John Casimir, Prince of Anhalt-Dessau |
| Birth Date: | 14 May 1606 |
| Birth Place: | Kassel |
| Death Place: | Dessau |
Agnes of Hesse-Kassel (14 May 1606 in Kassel - 28 May 1650 in Dessau) was a princess of Hesse-Kassel by birth and by marriage Princess of Anhalt-Dessau.
Agnes was a daughter of Landgrave Maurice of Hesse-Kassel (1572-1632) from his second marriage to Juliane of Nassau-Siegen (1587-1643), the daughter of Count John VII of Nassau-Siegen. She was raised together with her siblings. She spoke six languages and composed music.
On 18 May 1623 she married Prince John Casimir of Anhalt-Dessau (1596-1660). During the Thirty Years' War, she managed to soften the plight of Anhalt-Dessau by negotiating with the generals, both orally and in writing. She was considered a keen economist and mathematician. In 1645, she built a fortified house in Nischwitz, which was later developed into Oranienbaum Castle.
From her marriage Agnes had the following children:
married in 1659 to Princess Henriette Catherine of Nassau (1637-1708)
married in 1648 to Duke Christian of Brzeg (1618-1672)