Michael De Courcy Fraser Holroyd was born in London and educated at Eton College, though he has often claimed Maidenhead Public Library as his alma mater.

In 1964 he published his first book, a biography of writer Hugh Kingsmill, but his reputation was consolidated in 1967-68 with the publication of his life of Lytton Strachey (which playwright Christopher Hampton later used extensively when writing the screenplay for the 1995 film Carrington). Holroyd has also written biographies of Augustus John and a four-volume biography of George Bernard Shaw.

Holroyd acted as Chairman of the Society of Authors, 1973-83, and from 1985 to 1988 was president of the English branch of PEN. His awards include the 2001 Heywood Hill Literary Prize and the 2005 David Cohen Prize for literature. Holroyd was also President of the Royal Society of Literature from 2003 to 2008 and was knighted in the 2007 New Years' Honours List. His latest book, A Strange Eventful History (2008), recounts the 19th-century theatrical careers of Ellen Terry, Henry Irving and their children.

Holroyd is a Patron of Dignity in Dying.

He is married to author Dame Margaret Drabble.