Ian Frank George Milner (6 June 1911 – 31 May 1991) was a New Zealand Rhodes Scholar at New College, Oxford who had attended Waitaki Boys' High School. He was then a political scientist, a civil servant with the Australian Department of External Affairs in Canberra and with the United Nations in New York, and from the early 1950s a professor of English at Charles University in Prague where he became the friend and translator into English of the eminent Czech poet, Miroslav Holub.
He had been implicated in the 1954 Petrov Affair during which he was named by an Australian Royal Commission as a KGB agent. During his time at the Department of External Affairs, his code name was said to have been "Bur". Later when a New Zealand newspaper, Truth, labelled him "a Red menace", two universities that had invited him to lecture in New Zealand withdrew their invitation.
Ian Milner was the son of one of New Zealand's most respected headmasters, Frank Milner, of Waitaki Boys' High School in Oamaru, usually known as "the Man".
He was one of a group of five young New Zealand scholars who went to Oxford University in the 1930s and subsequently distinguished themselves in war and revolution;James Bertram, Geoffrey Cox, Dan Davin, and John Mulgan were the others.
Late in 1944, Milner was appointed to the Post-Hostilities Division (P-HD) of the Australian Government's then Department of External Affairs. In 1945, Milner allegedly stole a number of classified documents and passed copies of the documents to the Soviet embassy through an agent code-named KLOD, who was a key organiser of the Soviet Union's intelligence gathering activities in Australia and who was believed to be Walter Seddon Clayton.