Dorothea of Saxe-Altenburg (26 June 1601 in Torgau – 10 April 1675 in Altenburg), was a princess from the House of Wettin by birth and by marriage Duchess of Saxe-Eisenach.

She was born in Torgau, where her father ruled as regent of the Electorate of Saxony.

She was raised mostly at Lichtenburg Castle by Electress dowager Hedwig of Saxony.

[1] From 1620, she was a member of the Virtuous Society under the nickname die Freudige ("the Joyful").

In 1633, Dorothea left the Abbey and on 24 June she married in Weimar with her first cousin Duke Albert IV of Saxe-Eisenach (1599-1644).