Science Fiction and comedy are a natural mixture, since some of the wackiest ideas have come from even serious sci-fi movies. When the comedy is intentional, it can either flop hard or reach fantastic success. At Top2040, here are the top 20 sci-fi comedy movies that succeeded in being funny and entertaining:
1 - Time Bandits (1981) Terry Gilliam's masterpiece sci-fi comedy, starring John Cleese, Sean Connery, Michael Palin and many more top stars. A kid joins a band of dwarf pirates who jump from one time-period to another looking for treasure to steal.
2 - Galaxy Quest (1999) Aliens monitor Earth's TV, and discover a "Star Trek" like show, which they think is real. They come to get help from the show's cast, to defend their world from invaders.
3 - Paul (2011) Two guys on a tour of the US find an escaped alien, and help him find his ship. Well written and brilliantly acted, funny sci-fi movie.
4 - Weird Science (1985) Anthony Michael-Hall. Two teens create a hot Frankenstein monster "babe" in their bedroom, in classic 80s style.
5 - Attack the Block (2011) from the "Shaun of the Dead" people, a teen gang wards off an alien invasion. Highly recommended sci-fi comedy. A UK version of the US movie "The Watch" (Ben Stiller)
6 - The Hitchhiker's Guide to the Galaxy (2005) Based on the Douglas Adams novel. Not quite as good as the BBC series, but still a lot of fun to watch.
7 - The Man with Two Brains (1983) An under-appreciated role by Steve Martin, a brain surgeon who falls in love with a brain in a jar.
8 - The Adventures of Buckaroo Bonzai (1984) Petter Well (Robocop) is Banzai, who must save the world from inter-dimensional aliens. John Lithgow also stars.
9 - Mars Attacks! (1996) Directed by Tim Burton, starring Jack Nicholson, Michael J. Fox, Martin Short, more. Funny parody of alien invasion movies.
10 - Coneheads (1993) Dan Aykroyd and Jane Curtin star, based on the SNL skit. Kramer and Drew Carey even make cameo appearances.
11 - Ice Pirates (1984) Space opera parody.
12 - Short Circuit (1986) A robot named "Number 5" gains intelligence and escapes, with the help of his friends.
13 - Young Frankenstein (1974) Mel Brooks' only really successful and funny movie. Well done! Marty Feldman is especially funny.
14 - Sleeper (1973) Woody Allen and Diane Keaton, about a man who wakes 200 years in the future.
15 - Earth Girls Are Easy (1989)
16 - The Adventures of Baron Von Munchausen (1988) Another great Terry Gilliam movie.
17 - Zapped (1982) Scott Baio. Teen develops special kinetic powers in his lab at school.
18 - Men in Black (1997) Not as funny as the actors think it is, but it does have some good moments.
19 - Batteries Not Included (1987) Small extraterrestrial machines band together to save a neighborhood from invasion within Earth.
20 - Spaceballs (1987) Mel Brooks' semi-successful parody of Star Wars that kind-of misses the mark, and is rarely funny, but is worth a viewing for the few good lines in it.
Also check out at Top2040.com: Best Horror Comedy Movies
Honorable Mention: Evolution (2001), Howard the Duck (1986), Aliens in the Attic (2009).
Ghostbusters and the Frighteners are horror comedy movies, not sci-fi; otherwise they would have made the list.