Diary of a Madman may refer to:
Films Diary of a Madman (film), a 1963 horror film starring Vincent Price Diary of a Madman (1990 film), directed by Ronan O'Leary, cinematography by Walter Lassally
Literature "Diary of a Madman" (Nikolai Gogol), an 1835 short story by Nikolai Gogol "Diary of a Lunatic", an 1884 short story by Leo Tolstoy sometimes translated as "The Diary of a Madman" "Diary of a Madman" (Guy de Maupassant), an 1885 short story by Guy de Maupassant "Diary of a Madman" (Lu Xun), a 1918 short story by Lu Xun, also known as "A Madman's Diary" Diary of a Madman, a 2015 memoir by rapper Scarface
Music Diary of a Madman (album), by Ozzy Osbourne, or the title track "Diary of a Madman" (song), by Gravediggaz The Diary of a Madman (opera), a 1958 chamber opera by Humphrey Searle
See also Diary of a Maniac, a 1993 Italian drama film Diary of a Mad Old Man, a 1961 novel by Japanese author Jun'ichirō Tanizaki