A Life for the Tsar (Жизнь за царя in Russian), sometimes known as Ivan Susanin (Иван Сусанин), is an opera by Mikhail Glinka. The libretto is by Georgy Rosen . It was first performed on 9 December 1836 in Saint Petersburg.

This work is the first Russian nationalistic opera, and it was immensely succesful as soon as it premiered. It was the first opera with a Russian text, and treated the story of the the election of the first Romanov tsar, Mikhail I, and the expulsion of the armies of Poland from the country. Ivan Susanin is the hero of the opera, and the work is often performed under that name (its original title) in Russia, while in other countries it is generally known as A Life for the Tsar, a title suggested by Nicholas I after he viewed a rehearsal and expressed his enthusiasm for the piece.