One of the transitional elements of the show, used to bridge two scenes together, contains a sound bite of a man saying "Look out!" The man is O.J. Simpson, and comes from a now-infamous interview Simpson gave to Howard Stern on Stern's radio show, before Simpson's well-documented legal troubles.
Harvey's boss in Harvey Birdman is Phil Ken Seben. This is a homophone of sorts of "Falcon 7" the character who gave Birdman his assignments over a video link in the original Birdman and Galaxy Trio series.
Features cameos by many Hanna-Barbera cartoon characters, usually appearing as parody versions of "themselves". For example, one episode featured The Flintstones (1960) mixed with elements of The Sopranos (1999).
Several episodes of the series have alternate titles. Episode 104 ("Death By Chocolate" was originally titled "The Unabooboo" while episode 106 ("The Dabba Don") was originally titled "The Sopranostones".
The show was originally animated using digital ink and paint, but only for the first season. The series was later animated using Adobe After Effects and Flash, due to the animation studio having difficulty maintaining the fast pace of the show, and thus the production of episodes slowed down due to constant retakes. Thus, it makes Harvey Birdman, not only the most expensive spin-off to Space Ghost Coast to Coast, but also the most expensive Adult Swim original series at the time.