She was a daughter of Count Philip III of Hanau-Münzenberg and Countess Palatine Helena of Simmern.
On 15 June 1571 Dorothea married with Count Anton of Ortenburg (5 September 1530 – 23 May 1573), a member of the Aulic Council and governor of Heidenheim on behalf of Württemberg and son of Count Joachin of Ortenburg, who with his ally Frederick III, Elector Palatine established the Protestantism in his domains against the adjacent Roman Catholic Duchy of Bavaria ruled by Albert V. This marriage, in consequence, strengthened the Protestant cause in Germany and indirectly was seen as a threat to Bavaria.
Moreover, Dorothea had a dowry of 10,000 florins, huge amount needed by the Ortenburg family who was short of money at that time because of their fight against Bavaria and the Aulic Council expenses of Anton caused considerable additional costs.
Once betrothed, Anton and Dorothea where summoned at the court of the Elector Palatine in Heidelberg in May 1570, where the groom arrived from the Diet of Speyer.
Seven months later, on 1 December 1573, Dorothea gave birth a son, Frederick, who only lived four days.