Hans Fischer (July 27, 1881–March 31, 1945) was a German organic chemist and the recipient of the 1930 Nobel Prize for Chemistry.

He read chemistry and medicine, first at the University of Lausanne and then at Marburg. He graduated in 1904, and in 1908 he qualified for his M.D.
In 1913 he became a lecturer in physiology at the Physiological Institute in Munich.
In 1916 he became Professor of Medical Chemistry at the University of Innsbruck and from there he went to the University of Vienna in 1918.
From 1921 until his death he held the position of Professor of Organic Chemistry at the Technical University of Munich.
Fischer's scientific work was mostly concerned with the investigation of the pigments in blood, bile, and also chlorophyll in leaves, as well as with the chemistry of pyrrole from which these pigments are derived. Of special importance was his synthesis of bilirubin and haemin.