Ernst Otto Fischer is a German chemist.

He was born in Solln , near Munich, on 10 November 1918. His parents were Karl T. Fischer , Professor of Physics at the Technical College of Munich and Valentine née Danzer. He graduated in 1937 with Arbitur. Before the completion of two years' compulsory military service, the Second World War broke out, and he served in Poland, France and Russia. During a period of study leave, towards the end of 1941 he began to study Chemistry at the Technical College in Munich. Following the end of the War, he was released by the Americans in the autumn of 1945, and resumed his studies, graduating in 1949.

He became scientific assistant to Professor Walter Hieber in the Inorganic Chemistry Department, and worked on his doctoral thesis, "The Mechanisms of Carbon Monoxide Reactions of Nickel II Salts in the Presence of Dithionites and Sulfoxylates". After receiving his doctorate in 1952, he continued the study of transition metal and organo-metallic chemistry, writing a thesis on "The Metal Complexes of Cyclopentadienes and Indenes". He was appointed a lecturer at the Technical College in 1955, and in 1957 was appointed Professor at the University of Munich, then Senior Professor in 1959.

In 1964 he took the Chair of Inorganic Chemistry at the Technical College of Munich and in the same year was elected a member of the Mathematics/Natural Science section of the Bavarian Academy of Sciences. In 1969 he was appointed a member of the German Academy of Scientists, Leopoldina and in 1972 was given an honorary doctorate by the Faculty of Chemistry and Pharmacy of the University of Munich.

He lectured in the United States and many other countries on metallic complexes of cyclopentadienes and indenes, metal-p-complexes of six-ringed aromatics, mono-, di- and oligo-olefins and metalcarbonyl carbene and carbyne complexes. In 1969 he was Firestone Lecturer at the University of Wisconsin, in 1971 Visiting Professor at the University of Florida and in 1973 was the Arthur D. Little Visiting Professor at the Massachusetts Institute of Technology.

He has received many awards, and in 1973, together with Geoffrey Wilkinson received the Nobel Prize for his work on sandwich compounds .