South Park started in 1997 and is still going strong to this day. The show has evolved over the years and the type of comedy has changed from meaningless, juvenile absurdism to more advanced storylines and actual character development.
Throughout its impressively long run, South Park has had a handful of guests come to lend their talents to the animated show. This list ranks the best among them. They come from all corners of show business. It might seem uncharacteristic for some of these actors to appear in South Park, but they are not above making fun of themselves. Most consider it an honor to be a part of a cultural phenomenon, after all.
10 Sia
Season 18 features a subplot where Randy Marsh turns out to be Lorde. The song used to parody the pop singer is called Push. It is not sung by her, but instead by another famous pop singer, Sia.
She only confirmed that it was her the year after the 2014 episode aired. Lorde was said to appreciate the parody. Trey Parker is a talented musician and has written numerous songs for the show.
9 Elon Musk
People have varying opinions about Elon Musk. The man certainly loves playing himself in various projects, whether that be Machete Kills or the 20th season of South Park.
He appears in three episodes at the end of the season in a plot thread about a mission to Mars for which Cartman's girlfriend does research. It is a part of a rather tense finale involving shutting down the Internet
8 Jennifer Aniston
The third season premiere involves the kids going to a Costa Rican rainforest and having a terrible experience. The teacher on the field trip, Miss Stevens, is played by Jennifer Aniston.
The most fun part of the episode is hearing the actress scream obscenities. The episode is a reflection of Trey Parker's hatred for rainforests. The end of the episode goes as far to encourage its further destruction.
7 Robert Smith
The 12th episode ever is called "Mecha-Streisand" and features the pop singer turning into a giant robot and destroying the town. She is obviously not played by the real Barbara Streisand, but the frontman for The Cure Elliot Smith does play himself in the episode.
He spoke positively of the experience. Other celebrities parodied in the episode include Sidney Poitier and Leonard Maltin, though Smith is the only one voiced by the real person.
6 Cheech And Chong
The guest appearance by this legendary comedy duo in the episode "Cherokee Tampons" from season four is so special because it was the first time the two appeared in a work together for years. They did not record their lines together, however.
The episode is an obvious critique on holistic medicine, with the main peddler of the products literally going by the name Miss Information. The episode also features a shot live-action segment.
5 Joe Strummer
The 14th episode of season two, "Chef Aid", features guest appearances from a large variety of musicians. As the episode's name implies, it is a parody of numerous charity concerts that bring celebrities together to rally for a cause.
It is an eclectic mix of musicians as well, from Ween to DMX. Joe Strummer is the most surprising musical guest. The Clash was always super serious and political, so being involved in a parody is surprising.
4 Radiohead
"Scott Tenorman Must Die" from the fifth season is one of the most celebrated episodes of South Park. Cartman takes his ridiculous antics to an extreme by tricking a kid who wrongs him into eating his own parents in a bowl of chili.
As if this was not bad enough, Radiohead shows up and finds the crying boy and further berates him for crying. The band is played by the actual members of Radiohead.
3 Norman Lear
"I'm a Little Bit Country" sees Cartman going back and time and discovering how the founding fathers set the foundation for the United States. Norman Lear plays Benjamin Franklin and also served as a consultant on the episode.
He is not a famous actor, but Norman Lear is responsible for some of the most legendary television sitcoms of all time, including All in the Family, The Jeffersons, and Good Times.
2 Mike Judge
Even though Kenny dies all the time in the show's early years, his death in the South Park movie felt more permanent at first. It was a notable moment because it finally showcased Kenny without his hood.
Kenny's one line of clear words was done by Mike Judge, who is famous for creating such classic shows like Beavis and Butthead and King of the Hill. He also directed the cult films Office Space and Idiocracy.
1 George Clooney
George Clooney was the first notable guest star on South Park. What noble role was assigned to this legend of both the small and big screen? It was a few simple dog barks from Stan's dog Sparky.
George Clooney is a huge fan of South Park even before the show was on the air, showing his appreciation for the shorts Trey Parker and Matt Stone made as film students. George Clooney also plays a doctor in the movie, South Park: Bigger, Longer, and Uncut.