Katzmarek first became a member of the Bundestag in the 2013 German federal election. She is a member of the Committee on Economic Affairs and Energy. In 2019, she was elected as one of her parliamentary group’s whips, under the leadership of chairman Rolf Mützenich. In this capacity, she also joined the parliament’s Council of Elders, which – among other duties – determines daily legislative agenda items and assigns committee chairpersons based on party representation.