Don Juanism is a non-clinical term for the desire, in a man, to have sex with many different female partners; that is: a "seducer of women."

The name derives from Don Juan of opera and fiction, who seems in turn to have been patterned after the Spanish noble Don Juan Tenorio. The term satyriasis is sometimes used as a synonym for Don Juanism. The term has also been referred to as the male equivalent of nymphomania in women. Historian Carol Groneman has demonstrated that these terms no longer apply with any accuracy as psychological or legal categories of psychological disorder.

Psychologist Carl Jung believed that Don Juanism was an unconscious desire of a man to seek his mother in every woman he encountered. However, he didn't see the trait as entirely negative; Jung felt that positive aspects of Don Juanism included heroism, perseverance and strength of will. This aspect of the character is examined by Mozart and his librettist Da Ponte in their opera Don Giovanni, perhaps the best-known artistic work on this subject. To write their opera, Mozart and Da Ponte are known to have consulted with the famous libertine, Giacomo Casanova, the usual historic example of Don Juanism. Although not conclusively established, it is probable that Casanova attended the premiere of this opera, which was likely understood by the audience to be about himself. In a famous passage the philosopher Kierkegaard discusses Mozart's version of the Don Juan story.Albert Camus has also written on the subject.