Luther is a 1961 play by John Osborne that explored the forces that were involved in the life of Martin Luther, one of the instigators of the Protestant Reformation. Osborne was influenced by Erik Erikson's book, Young Man Luther, which had been published three years prior in 1958. In the play, Luther's reputed constipation plays a part in the course of his life and career. Osborne takes Luther to task for his Against the Murderous, Thieving Hordes of Peasants (1525), and its call for vigorous suppression of the peasants in the Peasants' Revolt (1524–1526). He has Luther give a philosophically and theologically good answer to the challenge, consistent with Luther's own thinking. This would seem to exculpate Osborne of any accusation of being totally one-sided against Luther. Luther seems to have been a disappointment to Osborne, since he could have followed through in his life as a revolutionary. He does have Johann von Staupitz, although at a time when the historical person would have been dead at least one year, telling Luther: "We owe so much to you."

Albert Finney created the role of Luther, which he performed at the Royal Court Theatre in London and the St. James Theatre on Broadway in New York City.

The play was made into a film starring Stacy Keach, Judi Dench, Maurice Denham, Hugh Griffith, Patrick Magee, and Robert Stephens in 1974.