Alien Autopsy: Fact or Fiction is a 1995 pseudo-documentary containing grainy black and white footage of a hoaxed alien autopsy. In 1995, film purporting to show an alien autopsy conducted shortly after the Roswell incident was released by British entrepreneur Ray Santilli. The footage aired on television networks around the world. Fox television broadcast the purported autopsy, hosted by Jonathan Frakes, on August 28, 1995, under the title Alien Autopsy: Fact or Fiction, and re-broadcast it twice, each time to higher ratings. The footage was also broadcast on UK's Channel 4, and repackaged for the home video market. The program was an overnight sensation, with Time magazine declaring that the film had sparked a debate "with an intensity not lavished on any home movie since the Zapruder film".

The program was thoroughly debunked. The autopsy footage was filmed on an inexpensive set constructed in a London living room. Its alien bodies were hollow plaster casts filled with offal, sheep brains, and raspberry jam. Multiple participants in Alien Autopsy stated that misleading editing had removed their opinions that the footage was a hoax. Santilli admitted in 2006 that the film was a fake, though he continued to claim it was inspired by genuine, but lost footage.

Alien Autopsy was derided in the media. In 1995, The X-Files featured alien autopsy footage that the skeptical Agent Scully decries as "even hokier than the one they aired on the Fox network". It was satirized again in the 1996 X-Files episode Jose Chung's From Outer Space. In 1998, Fox aired a new special, The World's Greatest Hoaxes and Secrets Revealed!, which debunked the 1995 Alien Autopsy footage. A fictionalized version of the creation of the footage and its release was retold in the comedy film Alien Autopsy (2006).