This is a list of every film that was the longest film for its ceremony each year at the Oscars. This list does not include non-competitive honorary awards.

Special Note: This will be using the length as shown on Letterbox, meaning the theatrical length, excluding any potential director's or extended cuts. So, for example, at the 74th Academy Awards, Lagaan: Once Upon a Time in India is marked as the longest, with its 224 minute length, despite the fact that Fellowship of the Ring's Extended Cut is 228 minutes long. This is because the original cut is only 179 minutes long.

Special Notes:
- All but 2 films have been over 2 hours long. the only exceptions are Grand Hotel (112 minutes) at the 5th Academy Awards and Eskimo (117 minutes) at the 7th Academy Awards.
- 45 of these movies have been over 3 hours long, for less than half at 45.9%
- Only 8 of these movies have been over 4 hours long, and only 3 have been over 5 hours long.
- Only 2 films have been over 6 and 7 hours long. Those 2 films are War and Peace (422 minutes) at the 41st Academy Awards and O.J.: Made in America (467 minutes) at the 89th Academy Awards. O.J. also stands as the longest film ever nominated and the longest film to ever win an Oscar.
- 43 of these 98 movies have been nominated for Best Picture, for less than half at 43.9%. Only 18 of those films have ended up winning.
- Cleopatra (248 minutes) is thus the longest film ever nominated for Best Picture, being nominated at the 38th Academy Awards