From 1946 to 1952, Müller-Hermann was a member of the Bremen State Parliament and from 1950 to 1952 Chairman of the CDU parliamentary group.

He was a member of the German Bundestag from January 1, 1952, when he succeeded Johannes Degener, until 1980.

He was elected to parliament in all electoral periods via the CDU's Bremen national list.

Biographisches Handbuch der Mitglieder des Deutschen Bundestages.

This biography article about a member of the Christian Democratic Union of Germany (CDU) is a stub.