Some of Maurice LaMarche's more prominent roles include:
- The Brain in Animaniacs and Pinky and the Brain
- Chief Quimby in Inspector Gadget
- LaMarche also plays Gadget himself these days. He got his start as Don Adams' singing double in Inspector Gadget Saves Christmas, and started doing the voice proper in Inspector Gadget's Last Case..
- George Wilson in Dennis the Menace
- Dr. Egon Spengler in The Real Ghostbusters and Extreme Ghostbusters
- Zoltan in Attack of the Killer Tomatoes!
- Dizzy Devil in Tiny Toon Adventures
- Balto in the sequels Wolf Quest and Wings of Change
- Aloysius 'Al' Vermin in Bonkers
- Verminous Skumm in Captain Planet and the Planeteers
- Jeremy Hawke and most of the male celebrities in The Critic
- Longhorn in Freakazoid!
- Handy and The Evil Midnight Bomber What Bombs at Midnight (yeah, baby!) in The Tick
- Reverend Thomason in King of the Hill
- Mortimer Mouse in House of Mouse
- Big Bob Pataki in Hey Arnold!
- Master Fung in Xiaolin Showdown
- Father in Codename: Kids Next Door
- Stan Freezoid and about half of the classic Hanna-Barbera characters in Harvey Birdman, Attorney at Law
- The Chief in Tak and the Power of Juju
- Principal Pixiefrog in My Gym Partner's A Monkey
- Morbo, Kif, Calculon, Lrr, Hedonismbot and others in Futurama (in a commentary, LaMarche admits that Lrr, Morbo and the Horrible Gelatinous Blob are basically all the same voice with different amounts of grumbling)
- Mr. Freeze and Calender Man in Batman: Arkham City
- The Grand Master Wizard in Adventure Time
- Avocado Soldier in the Axe Cop motion comic
- The Garbageman and Mordac, Preventer of Information Services in the animated adaptation of Dilbert
- Sixgun in The Transformers
- Chief Charlie Burns in Transformers Rescue Bots
- Doctor Doom in Ultimate Spider-Man and Avengers Assemble
- Vincent Van Ghoul in Scooby-Doo! Mystery Incorporated
- Tapper in Wreck-It Ralph
- The king of Arendelle in Frozen.
- And, of course, Orson Welles nearly any time the guy's depicted in animation.*
Gee, Mr. LaMarche, what do you want to do tomorrow night?
The same thing we do every night, Paulsen...Try to take over the—
Stingers do not work that way! Good night!They're funny, they're Paulsen and LaMarche, Marche, Marche, Marche, Marche!