Gerhard Ertl (born 10 October 1936) is a German physicist and a Professor emeritus at the Department of Physical Chemistry, Fritz-Haber-Institut der Max-Planck-Gesellschaft in Berlin, Germany. He won the 2007 Nobel Prize in Chemistry. The award, worth SEK 10 million (US$1.7 million, GB£1.15 million), was announced on Ertl's 71st birthday.

After completing his PhD, he became an assistant and lecturer at Technical University of Munich (1965–1968).
From 1968 to 1973, he was Professor and Director at Technical University of Hannover. Then, he became a Professor at Institute for Physical Chemistry, Ludwig Maximilians University of Munich (1973–1986).
During the 1970s and 80s, he was also a Visiting Professor at the California Institute of Technology, the University of Wisconsin–Milwaukee and the University of California, Berkeley.
In 1986 he became professor at the Free University of Berlin and at the Technical University of Berlin. He was director at the Fritz Haber Institute of the MPG from 1986 till his retirement in 2004. He became professor at the Humboldt University of Berlin in 1996.
He won the Wolf Prize in Chemistry in 1998 along with Gabor A. Somorjai of the University of California, Berkeley for "their outstanding contributions to the field of the surface science in general and for their elucidation of fundamental mechanisms of heterogeneous catalytic reactions at single crystal surface in particular."