Deirdre Bair (born June 21, 1935) is an American writer and biographer. She is the author of six works of nonfiction.
She received a National Book Award for Samuel Beckett: A Biography (1978). Her biographies of Simone de Beauvoir and C. G. Jung were finalists for the Los Angeles Times Book Prize. Her biographies of Anaïs Nin and Simone de Beauvoir were chosen by the New York Times as “Best Books of the Year”, and her biography of Jung won the Gradiva Award from the National Association for the Advancement of Psychoanalysis. Her most recent book, Calling It Quits, examines late-life divorce and starting over and has been profiled on CBS’s The Early Show, NBC's The Today Show, the Brian Lehrer radio show and on CBC Canada. She published a biography of New Yorker cartoonist and artist Saul Steinberg in 2012 and a biography of Chicago mobster Al Capone in 2016, using never-revealed sources from his family.
She has been awarded fellowships from (among others) the John Simon Guggenheim Memorial Foundation, Rockefeller Foundation and the Radcliffe Institute for Advanced Study (then named the Bunting Institute). She is a literary journalist who writes frequently about travel, feminist issue, and cultural life. A former professor of comparative literature, she writes and lectures internationally. She divides her time mostly between New York and Connecticut.