Georg Balthasar Metzger (23 September 1623 – 9 October 1687) was a German physician and scientist notable as one of the four founding members of the German Academy of Sciences Leopoldina in Schweinfurt.In 1646 Metzger obtained the Magister Artium degree from the University of Jena under Gottfried Möbius with a thesis entitled: Suppressionem mensium.