Kathleen Mildred Burk (born March 1946) is Professor Emerita of Modern and Contemporary History at University College London. Her field of research is international history, especially politics, diplomacy and finance.

Burk grew up in a California grape farming family. She has undergraduate degrees from University of California at Berkeley and Oxford University at St Hugh's College, and a D.Phil. from Oxford University, where she studied under A. J. P. Taylor. Her early books focused on economic diplomacy and were driven by her insight that “While governments come and go, the need for money is inexorable.”

After finishing her studies, she was Tutorial Assistant in Modern History at Dundee University (1976–77). From 1977–1980 she was as a Rhodes Research Fellow at Oxford. From 1980-1992 she was a Lecturer in History and Politics at Imperial College London. She started at University College London in 1990–1992, becoming Reader in Modern and Contemporary History in 1993 and a Professor in 1995. In the mid-nineties, only 7 per cent of the professors there were women.

A 2013 issue of the academic journal Diplomacy & Statecraft was devoted to essays in her honour. She is a fellow of the Norwegian Academy of Science and Letters.