Ralph Wiggum is a particularly well known character on the long-going animated show The Simpsons. An 8 year old boy in Lisa Simpson's 2nd Grade class with brown pants, a blue long sleeve shirt, stringy hair cut in a bowl-cut, and with a rotund build. He is the only child of Springfield's Chief of Police, Clancy Wiggum, who seems to love his son quite a bit although he can be seemingly oblivious to Ralph's situations.

Ralph plays the role of the unintentional funny guy and resident oddball. He has been made famous for his weird behavior and seemingly random non-sequitor dialogue. His behavior ranges inconsistently from childish, to dense and oblivious, to vaguely autistic or generally having a mental defect of some kind, to simply being different and weird. He can be many things, but the one consistency is that it is never specific and for this Ralph brings a great deal of the show's random element. His erratic ways range from oblivious attempts at grasping the situation to nonsensical actions.

Ralph's character may possibly however have a double meaning. While he is famous for his seemingly dense or crazy behavior, he may be one of those children who's not what he may seem to be at first glance. Hints have been dropped over the years in various media to subtley suggest that unknown to most others, he has great potential in artistic endeavors such as singing, performing, acting, and perhaps even painting. This like everything with the character ranges variably as the situation calls for.

From his humble beginnings as a mere background character, Ralph has come his own to have many famous and often quoted scenes in the show. Particular favorites are his scenes in the episode Lisa's Rival, the majority of his role in I Love Lisa, proclaiming himself the state of Idaho in $pringfield, seeing an imaginary pyromaniacal Leprechaun in This Little Wiggy, and visiting a rather disturbingly passionate dentist in Last Exit to Springfield to name a few. The episode Burns, Baby Burns houses perhaps his most quoted line, "That's Unpossible!" The rock band Bloodhound Gang composed a well known song named after the character, "Ralph Wiggum", whose lyrics are comprised entirely of nothing but quotes the character has spoken over the years.

Although he has made many appearances, thus far he has been the center of two episodes: I Love Lisa (season 4), and This Little Wiggy (season 9). He is scheduled to be the focus of a third episode in season 19.