Diane Corner (born 29 September 1959) is a former British diplomat who is deputy head of the United Nations Multidimensional Integrated Stabilization Mission in the Central African Republic.
Diane Louise Corner was educated at Winchester County High School for Girls, Peter Symonds College and the University of Bristol. She joined the Foreign and Commonwealth Office (FCO) in 1982 and served at Kuala Lumpur, Berlin, Harare and in the Cabinet Office on secondment, as well as in the FCO. In 2000 she completed the Senior Course at the NATO Defence College in Rome. She was acting High Commmissioner to Sierra Leone 2008–09, High Commissioner to Tanzania 2009–13 and Ambassador to the Democratic Republic of Congo and Republic of Congo 2013–14. She was appointed to her present post in July 2014 by United Nations Secretary-General Ban Ki-moon.