I due Foscari (The Two Foscari) is an opera in three acts by Giuseppe Verdi to an Italian libretto by Francesco Maria Piave, based on a historical play, The Two Foscari by Lord Byron.

After his success with Ernani, Verdi received a commission from Rome's Teatro Argentina and he went to work with Piave in considering two subjects, one of which eventually became this opera. I due Foscari was given its premiere performance in Rome on 3 November 1844 and was generally quite successful, although not on the scale of Ernani, which remained Verdi's most popular opera until Il trovatore in 1853.

Today, Foscari is revived occasionally and its fortunes have been helped by the interest taken by tenor Plácido Domingo in singing baritone roles. He has already performed the role of the Doge in Los Angeles in 2012, in Valencia in early 2013, and he will do so again in Vienna in 2014.