Dagmar Ziegler (born 28 September 1960) is a German politician of the Social Democratic Party (SPD) who served as a member of the Bundestag from the state of Brandenburg from 2009 until 2021.

[2] From 2009 until 2013, she was Member of the Bundestag FOR Prignitz – Ostprignitz-Ruppin – Havelland I in north-western Brandenburg State, and served as deputy chairwoman of the SPD parliamentary group under the leadership of chairman Frank-Walter Steinmeier.

In the negotiations to form a Grand Coalition of Chancellor Angela Merkel's Christian Democrats (CDU together with the Bavarian CSU) and the SPD following the 2013 federal elections, Ziegler was part of her party's delegation in the working group on families, women and equality, led by Annette Widmann-Mauz and Manuela Schwesig.

From 2014, Ziegler served on the parliament’s Council of Elders, which – among other duties – determines daily legislative agenda items and assigns committee chairpersons based on party representation.

In December 2019, Ziegler announced that she would not stand in the 2021 federal elections but instead resign from active politics by the end of the parliamentary term.