A Beautiful Mind is a 1998 unauthorized biography of Nobel Prize-winning economist and mathematician John Nash by Sylvia Nasar, professor of journalism at Columbia University.

The book was adapted into the film A Beautiful Mind in 2001 directed by Ron Howard and starring Russell Crowe as Nash.

Starting with his childhood, the book covers Nash's years at Princeton and MIT, his work for the RAND Corporation, his family and his struggle with schizophrenia.

The book is a detailed description of many aspects of Nash's life, including the nature of his mathematical genius, and a close examination of his personality and motivations.

John Milnor notes the ethical issues posed by the book, an unauthorized biography and prepared without the cooperation of the subject.