Uta Zapf was a member of the German Bundestag from 1990 to 2013.
There, she served as chairwoman of the Sub-Committee on Disarmament, Arms Control, and Nonproliferation (1998-2013) and was member of the Committee on Foreign Affairs. Her work in Parliament focused on disarmament, arms control, security policy, crisis prevention, South Eastern Europe (Turkey, Stability Pact for South Eastern Europe), Afghanistan, and Belarus. She also served as co-president of the Parliamentarians for Nuclear Non-proliferation and Disarmament.
In 2003, she was one of the co-founders of the "One World" ("Eine Welt") forum initiated by the Social Democrats in Hesse.