Arthur R. Butz is an American Holocaust revisionist and professor of electrical engineering at Northwestern University. He has been tenured there since 1974.

In 1976, Butz wrote The Hoax of the Twentieth Century: The Case Against the Presumed Extermination of European Jewry, in which he asserted that the Holocaust (a) did not occur and (b) has been deliberately contrived in order to justify the creation of the state of Israel. Hoax is one of the documental keystones of the so-called "revisionist" movement.

Most recently, Butz attracted attention when he issued a statement in which he agreed with Iranian President Mahmoud Ahmadinejad's alleged statement that the Holocaust is a "myth." In a press release dated December 18, 2005, Butz wrote, "I congratulate him [Ahmadinejad] on becoming the first head of state to speak out clearly on these issues [the alleged fabrication of the Holocaust], and regret only that it was not a Western head of state. His political remarks receive no comment on my side. By 'political remarks' I mean those that deal with questions of what ought to happen now" (Ahmadinejad had called for Israel to be "wiped off the map").

Butz's remarks have evoked the ire of a considerable majority of Northwestern affiliates, and the university's president, Henry Bienen, issued a statement condemning Butz's viewpoints, saying they are an "embarrassment to Northwestern."

Sixty-one of Butz's own colleagues in the department of electrical engineering and computer science published an official censure in February, 2006, calling for Butz to "leave our Department and our University and stop trading on our reputation for academic excellence."