(to be updated as more names and descriptions are found or remembered)
- Dr Jordan Edilstein - "Camp Refoogee" - College professor: IQ = 140, Near sighted, once spent an experimental weekend with Alex Ginsberg. A Hebrew who had a successful selling book. Head of the Political Science Department at Harvard (later the Economics Department). Married to Amanda Lane (played by Francine) for 17 years.
- Professor Baxter - "Iced, Iced Babies" - College professor at Goff Community College teaching literature (and life). "I pretend to teach them, but it's really they who pretend to teach me." He is highly respected by his students, especially Ethan, who later turn psychotic and tries to kill the professor and Hayley.
- "...Well then I'm taking away 50 points from Griffindor!"
- Krispy Kreme McDonald's - "American Dream Factory" - Apparently, because Roger has no bones in his arms, he is a natural on the drums. When Steve looks for a new drummer for his band, Roger auditions as this alter ego. Later, Roger kicks Steve out of the band and becomes lead singer, covering public domain songs with Steve's band.
- Chilly - "42-Year-Old Virgin" - Roger uses this persona at a poker night with Stan and some of his co-workers. He never seems to get much luck and his best hand is a pair of threes.
- Horse Renoir - "Joint Custody" - Roger's bounty hunter persona he used when going after Jeff. Born in the bayou, some say the hell-spawn of a whore and a prostitute.
- Kevin Bacon - "Four Little Words" - Roger pretends to be Kevin Bacon when Hayley and Steve give him a replica of Bacon's nose. He abuses his star power to get as much free stuff as he can. Roger is forced to give up this disguise after being involved in a hit-and-run. Luckily, police mistake him for the real Kevin Bacon, who is subsequently arrested.
- Scotch Bingington - "Spring Break-Up" - Roger creates the character of Scotch Bingington in order to become the king of spring break.
- Laura Vanderbooben - "Stanny Slickers 2: The Legend of Ollie's Gold" - Roger pretends to be a woman so he can be sexually harrassed and then paid off by the company at which he gains employment.
- "Looking for something glazed and BAD for you?"
- Luke Fondleberg - "Stanny Slickers 2: The Legend of Ollie's Gold" - Roger's male character used in hopes of winning a sexual harassment lawsuit.
- "Any hot pieces of tail around this office that like a good groping?"
- Parker Peters - "Office Spaceman" - Roger pretends to be a photographer in order to sell pictures of himself to a newspaper. He is eventually hired by the CIA. (a parody of Peter Parker)
- Predator - "Joint Custody" - Roger considered dressing as this when going after Jeff. Unfortunately, Stan left while he was still deciding, so he was forced to seek an alternative.
- Mr Mustachos - "Chimdale" - Roger adopts this identity to take Francine to an expensive spa weekend in Chimdale, which he won as a prize in a radio contest (however it was only for two, so Haley was sneaked in via a suitcase). When the spa-detective becomes suspicious, Roger and Francine must pretend to be a couple.
- "Don't Portuguese out on me!"
- Cousin Phil - "Oedipal Panties" - Roger disguises himself as this when Stan's mother Betty comes to visit.
- Sholanda Dykes - "The One That Got Away - One of Roger's personas that works at AT&T.
- Warren Beanstalk - "Daddy Queerest" - Once sat in an ally buying booze for minors. He his reasons mind you! Namely that he made quite a nifty profit. Bought himself a boom box, a folding chair, and a dog named Pepper. Ok, he hit a little girl and stole the dog. He later gave up his enterprise when Steve's own experience of "beer goggles" showed what atrocities can happen when children drink.
- "Oh, you'll feel better after a few beers. You're driving."
- Sidney Huffman - "The One That Got Away - One of Roger's personas that became independent and developed a separate life. Roger originally created him to steal a pair of gloves from a store. He is a devout Christian who never drinks or smokes, works as a Bible manufacturer, and is in a loving, commited relationship with Judy Panawitz. Roger ends up killing him, his reasoning being that he was "a good egg, and that cramps my style."