Wilkinson was born at Todmorden in Yorkshire, and educated at Imperial College, London; after spending World War II working in North America on the development of the atomic bomb, he finally obtained his PhD in 1946. He later worked at the Massachusetts Institute of Technology and at Harvard, before being elected to the chair of inorganic chemistry at Imperial College, a post he held from 1956 until 1988. He was knighted in 1976.

Wilkinson is noted for his studies of inorganic complexes. He shared the Nobel Prize for chemistry in 1973 with Ernst Fischer for work on ‘sandwich compounds’. A theme of Wilkinson's work in the 1960s was the study and use of complexes containing a metal–hydrogen bond. Thus complexes of rhodium with triphenyl phosphine (C₆H₅)₃P) can react with molecular hydrogen. The compound RhCl(P(C₆H₅)₃), known as Wilkinson's catalyst, was the first such complex to be used as a homogeneous catalyst for adding hydrogen to the double bonds of alkenes (hydrogenation). This type of compound can also be used as a catalyst for the reaction of hydrogen and carbon monoxide with alkenes (hydroformylation). It is the basis of industrial low-pressure processes for making aldehydes from ethene and propene.