The pilot episode was created in but was aired on Cartoon Network Video  in as part of the show project The Cartoonstitute , while the series premiered on September 2, On July 25, , the series was renewed for a second season,  which premiered on March 5, On March 30, , it was reported that the series had been renewed for fourth and fifth seasons by Cartoon Network,  but in a different mode: they decide to split in half the already-ordered 52 episode-long second season, rebranding the first half as "season two" and the second half as "season three. The series concluded on June 30, after the series finale "Uncle Grandpa: The High School Years" with 5 seasons and a total of episodes. When the kid named Belly voiced by Zachary Gordon experiences difficulties with putting on his shirt due to his big belly getting in the way, Uncle Grandpa tries to make it up to him by going inside a Night Wolf shirt and teaching him about the benefits of having a big belly.
Cartoon Network 's first original series that wasn't based on an already existing character or an anthology series. Show , a shorts showcase for Hanna-Barbera employees The Powerpuff Girls was made under the same circumstances. Tartakovsky and Craig McCracken worked on both shows. Dexter is a boy genius with an unplaceable Central European accent , thick-rimmed glasses and a gigantic laboratory in his bedroom.
Pizza J. Stevens is a major character in Uncle Grandpa. He is a walking and talking slice of pizza who believes he is the coolest slice of pizza in the world. He sometimes likes to refer to himself in the third person. Despite the fact he is full of himself and portrays himself to be this way, he would really be lost without his friends.