Manfred Eigen (born May 9, 1927, Bochum) is a German biophysicist and a former director of the Max Planck Institute for Biophysical Chemistry in Göttingen. In 1967, he received, together with Ronald George Wreyford Norrish and George Porter, the Nobel Prize in Chemistry.

In 1967, Eigen was awarded, along with Ronald George Wreyford Norrish and George Porter, the Nobel Prize in Chemistry.
In addition, his name is linked with the theory of the chemical hypercycle, the cyclic linkage of reaction cycles as an explanation for the self organization of prebiotic systems, which he described with Peter Schuster in 1979.
He received his PhD at the University of Göttingen and has been former director of the Max Planck Institute for Biophysical Chemistry in Göttingen. He is an honorary doctor of the TU Braunschweig. From 1982 to 1993, Eigen was president of the German National Merit Foundation.