Bruce Michael Duffy (born June 9, 1951) is an American author.
He is best known for his novel The World As I Found It, a fictionalized account of the life of Ludwig Wittgenstein, a prominent 20th century philosopher.
In 1988, Duffy won a Whiting Award and received a Guggenheim Fellowship.
Joyce Carol Oates named "The World As I Found It" as one of "five great nonfiction novels," calling the book "a bold and original work of fiction" and "one of the most ambitious first novels ever published" (Salon.com).