"La donna è mobile" (The woman is fickle) is the Duke of Mantua's canzone from the beginning of act 3 of Giuseppe Verdi's opera Rigoletto (1851).
The canzone is famous as a showcase for tenors. Raffaele Mirate's performance of the bravura aria at the opera's 1851 premiere was hailed as the highlight of the evening.

Before the opera's first public performance (in Venice), the song was rehearsed under tight secrecy: a necessary precaution, as "La donna è mobile" proved to be incredibly catchy, and soon after the song's first public performance, every gondolier in Venice was singing it.

As the opera progresses, the reprise of the tune in the following scenes exemplifies a sense of confusion, as Rigoletto realizes that from the sound of the Duke's lively voice coming from within the tavern (offstage), the body in the sack over which he had grimly triumphed, was not that of the Duke after all: Rigoletto had paid Sparafucile, an assassin, to kill the Duke, but Sparafucile had deceived Rigolleto by indiscriminately killing Gilda, Rigoletto's beloved daughter, instead.
The song is an irony, as no character in the opera presents traits associated with rationality; every character may be considered callous and mobile ("inconstant").