The following is an alphabetical list of Dexter's Laboratory-related sightings and references in other media.
In the episode "The Contest" (Season 4, episode 4), Arthur, Muffy, Buster, Francine, Binky, and the Brain are all sharing stories. The Brain's story, "Hair Growth Formula", is a parody of Dexter's Laboratory. It featured the Brain as Dexter, Francine and Muffy as look-alikes of Dee Dee and Mee Mee, and Arthur as the Brain's lab assistant.
In the episode Mystery Science Fair 201X, Dendy shows KO her secret lab by stepping inside her locker and pressing a secret button.
While there, KO sees an invention and grabs it. Before he says; "Ooh. What does this button do?", Dee Dee's catchphrase, Dendy quickly takes her invention from him.
When KO destroys Dendy's inventions, she yells out, then tells KO to "get out of her observatory", the same way Dexter does to Dee Dee. KO also laughs in a similar manner to Mandark.
One other thing to note is that Dendy's walking sound is exactly similar to the walking sound Dexter makes.
After the credits, the tagline reads; "With apologies to the crew of Dexter's Laboratory :)", noting how this show was influenced by Dexter's Laboratory.
In the episode "Powerpuff Bluff", Dexter is one of the many students seen taking a nap at Pokey Oaks Kindergarten.
Dexter makes a cameo appearance in the episode "Uh Oh Dynamo".
In the episode "Criss Cross Crisis", while Professor Utonium tries to get everyone's bodies back to normal, Dexter was seen in place of Ms. Sara Bellum.
In the episode"Forced Kin", Dexter watches Mojo Jojo as he beats down the Alien Leader.
In the episode "Imaginary Fiend", Bubbles suggests sending Koosalagoopagoop to beat up Mike's imaginary friend. However, Buttercup declines her request saying; "Nobody likes that Koos jerk!"
In one episode, Samurai Jack and Ashi are both walking down a hallway. Jack is holding a remote in one hand and presses a button. When nothing happens, he presses it repeatedly, much like how Dexter does in the opening for Dexter's Laboratory.