22. Clarence (April 14, 2014 – present)

Clarence is created by Skyler Page for Cartoon Network. The show centers on a young boy named Clarence and his two best friends Jeff and Sumo.

The pilot aired after the 2014 Hall of Game Awards show on February 17, 2014. The series officially premiered on April 14, 2014 and was seen by approximately 2.3 million viewers, outperforming shows in its same demographic in the time slot. The series' pilot was nominated for a Creative Arts Emmy Award. The third season premiered on February 10, 2017 and will be the series' final season.

21. Time Squad (June 8, 2001 – November 26, 2003)

Time Squad was created by Dave Wasson for Cartoon Network. The show centers on the adventures of Otto Osworth, Buck Tuddrussel, and the robot Larry 3000, a trio of hapless "time cops" living in the far distant future who travel back in time attempting to correct the course of history. During their adventures, they run into major historical figures such as Julius Caesar, Abraham Lincoln, Sigmund Freud, Leonardo da Vinci, the Founding Fathers, and Montezuma, who have taken a drastically different course of life than history dictates. The mission of the Time Squad is to guide these figures onto the correct path and ensure the integrity of the future.

The series premiered during Cartoon Network's marathon block "Cartoon Cartoon Summer" on June 8, 2001, and ended after two seasons on November 26, 2003, airing 26 episodes in total (13 episodes in each season).

20. The Marvelous Misadventures of Flapjack (June 5, 2008 – August 30, 2010)

The Marvelous Misadventures of Flapjack was created by Thurop Van Orman for Cartoon Network. It stars creator Thurop Van Orman as the voice of Flapjack, a naïve young boy who was raised by a whale named Bubbie and is mentored by a salty sea pirate called Captain K'nuckles. Together the trio spend their days in Stormalong Harbor, where most of the show takes place, whilst on the search for the elusive Candied Island.

It aired for three seasons for a total of 92 episodes, from June 5, 2008, to August 30, 2010. Five shorts from July 27, 2007 to August 24, 2007 were shown as part of Cartoon Network's Wedgies in 2008, and have a shorter length (about five minutes) than a standard episode (about 22 minutes, without commercials).

19. We Bare Bears (July 27, 2015 – present)

Uncle Grandpa was created by Peter Browngardt for Cartoon Network. The show centers on the magical uncle and grandpa who is the uncle-grandpa and brother-dad of every child and adult in the world. He stops by children's houses every day to see how they are doing. The children he visits have a problem of their own and Uncle Grandpa tries to help them through a series of chaotic and surreal misadventures.

The series premiered on September 2, 2013 and concluded on June 30, 2017 after the series finale "Uncle Grandpa: The High School Years" with 5 seasons and a total of 153 episodes.

A crossover special between Uncle Grandpa and Steven Universe was aired as an episode of the latter series' second season on 2 April 2015. Conceived of by the creator of the latter series, Rebecca Sugar, the episode has Uncle Grandpa teach Steven how to bear a shield from his gemstone. Nearly two million viewed the episode, which received acclaim from critics.

In the episode, "Pizza Eve", (aired on April 16, 2016) there was a segment where Uncle Grandpa gives out Oscars to other Cartoon Network shows! Including Steven Universe, Clarence, Powerpuff Girls, Adventure Time, Ben 10, etc.

18. Ben 10 (December 27, 2005 – present)

Ben 10 is created by Man of Action Studios for Cartoon Network. The franchise centers on a boy named Ben Tennyson who acquires a watch-like alien device (the Omnitrix) which allows the wearer to transform into ten different alien creatures. The franchise has four movies, all of which aired on Cartoon Network between August 2007 and March 2012. With a 12-year old franchise, it is the longest Cartoon Network original series to date.

Ben 10 was originally named "10 Ben" when it featured on the channel Boomerang, It was later changed to Ben 10 in 2006 when the show was transferred to Cartoon Network.

17. Camp Lazlo (July 8, 2005 – March 27, 2008)

Camp Lazlo was created by Joe Murray for Cartoon Network. The show centers on Lazlo, a spider monkey who attends a Boy Scout-like summer camp with a cast of anthropomorphic animal characters.

The series premiered on July 8, 2005 at 8:00 p.m. ET/PT with five seasons, 61 episodes, and an hour-long television special.

16. Cow and Chicken (July 15, 1997 – July 24, 1999)

Cow and Chicken was created by David Feiss for Cartoon Network. The show centers on the surreal adventures of two funny animal siblings, Cow and Chicken. They are often antagonized by the Red Guy, who poses as various characters to scam them.

The series premiered on July 15, 1997. Originally, Cow and Chicken was attached to another segment called I Am Weasel, which was later spun off into its own half-hour series on June 10, 1999. Cow and Chicken has a total of 52 episodes in 4 seasons. It is one of only two Cartoon Cartoons original series that was owned by Warner Bros. Animation, the other one being I Am Weasel.