Alien cartoon characters are, in my opinion, the most fun category in all of animation. Writers don’t have to follow any rules. The alien can be a tiny green murder bean, a sentient blob, a four-foot Roman with a bucket on his head, or a koala that loves Elvis. It all works.
Here’s my honest ranking of the most iconic alien cartoon characters ever animated, from the lovable ones you want to hug to the conniving ones who keep trying to destroy Earth on a budget.
Quick list: The most iconic alien cartoon characters include Stitch, Marvin the Martian, Roger from American Dad, the Toy Story Aliens, Kang and Kodos, Invader Zim, ALF, The Great Gazoo, Starfire, the Crystal Gems, Mooncake, Star Butterfly, Wander, and E.T. The full ranking is below.
14Stitch – Lilo & Stitch (2002-present)
Experiment 626. Genetically engineered to destroy entire cities. Crash-landed in Hawaii. Got adopted by a small girl. Learned about family. Cried about Elvis. Stitch is the GOAT of cartoon aliens, no debate.
If you need more proof, check out my full breakdown on his alien handler Pleakley, who is, weirdly, also one of the best alien characters Disney has ever made.
13Marvin the Martian – Looney Tunes (1948-present)
Marvin is the most polite genocidal alien in animation history. He wears a Roman soldier outfit. He carries an Illudium Q-36 Explosive Space Modulator. He keeps trying to blow up Earth because it ruins his view of Venus.
Voiced originally by Mel Blanc, Marvin’s whole appeal is that he is calm. Bugs Bunny screams. Daffy panics. Marvin just quietly explains that he is going to delete your planet now, thank you.
Trivia: Marvin doesn’t actually have a face. The eyes you see are dots on his helmet. That’s why he’s so unsettling and so funny at the same time.
12Roger – American Dad! (2005-present)
Roger is a chaotic, narcissistic, hard-drinking gray alien who lives in the Smith family attic and adopts a new identity every episode. He has thousands of personas, hundreds of costumes, and zero ethics.
Voiced by Seth MacFarlane, Roger is basically American Dad‘s entire reason for existing at this point. He’s the show.
11The Toy Story Aliens (Little Green Men)
“OoOoOoOoh!”
The three-eyed Squeeze Toy Aliens from Pizza Planet have one personality trait (worship the claw) and they commit to it 100%. That’s all you need. They’re perfect.
They’ve been in every Toy Story movie, every short, every theme park ride, and every piece of Pixar merchandise ever made. The claw chose them.
10Kang and Kodos – The Simpsons (1990-present)
Kang and Kodos are the one-eyed, tentacled, drooling aliens from Rigel VII who show up almost every Halloween in The Simpsons‘ “Treehouse of Horror” specials.
Their schemes always fail. Their laughter is unsettling. Their tentacles are dripping with what I assume is concerning levels of saliva. And the show would be worse without them.
9Zim, GIR, and Gaz – Invader Zim (2001-2006)
Zim is a tiny green Irken invader sent to conquer Earth. His robot sidekick GIR is malfunctioning, addicted to tacos, and possibly the funniest character on the show.
Jhonen Vasquez’s creation is one of the all-time great cult cartoons. The fact that GIR’s love of waffles became a defining piece of 2000s internet humor tells you how influential this show was.
Small correction: Gaz isn’t actually an alien. She’s Dib’s human sister. She still belongs on this list because she’s terrifying and that’s its own form of alien energy.
8ALF – ALF: The Animated Series (1987-1989)
The Alien Life Form from planet Melmac. Voiced and puppeteered by Paul Fusco. Best known for: eating cats, wisecracking, and being one of the most marketable characters of the 1980s.
The Saturday morning animated spin-off was an actual prequel to the live-action show, set on Melmac before it exploded. ALF: deeper lore than you remember.
7The Great Gazoo – The Flintstones (1965-1966)
Gazoo is a small green alien from Zetox who was banished to prehistoric Earth for inventing a doomsday device. He floats around in a clear helmet, calls Fred and Barney “dum-dums,” and is only visible to them and small children.
He was introduced in the final season of The Flintstones in 1965, and fans were extremely split on him. Some loved the absurdity. Some thought he ruined the show. I’m in camp “absurd and fun.” Sue me.
6Starfire – Teen Titans (2003-2006)
Princess Koriand’r of Tamaran, better known as Starfire. She can fly. She shoots energy from her hands. She is constantly confused by Earth customs in the most endearing way possible.
Voiced by Hynden Walch, Starfire became one of the most beloved DC characters of the 2000s thanks to Teen Titans. Her habit of taking Earth idioms literally (“I will pour my heart out, where is the bowl”) is some of the best alien-on-Earth comedy ever written.
5The Crystal Gems – Steven Universe (2013-2020)
Garnet, Amethyst, Pearl, and Steven are the Crystal Gems, an interstellar group of gem-based aliens protecting Earth from their own species’ colonial empire.
It’s heavier than it sounds and lighter than it sounds at the same time. Steven Universe rewrote the rules for what alien characters could be on a kids’ show, and the Crystal Gems are the reason.
4Mooncake – Final Space (2018-2021)
Mooncake looks like a friendly green dumpling with huge eyes. Mooncake is also a planet-destroying weapon. Both of these things are true at the same time, and the show absolutely earns that contrast.
Created by Olan Rogers, Mooncake is proof you can make an adorable creature emotionally devastating without ever giving it real dialogue.
Heads up: If you watch Final Space, the show ended on a cliffhanger after being canceled. Just know that going in.
3Star Butterfly – Star vs. the Forces of Evil (2015-2019)
Technically Star isn’t an alien, she’s interdimensional. But Mewni is functionally another world, she has magic powers, and she lives on Earth as an exchange student, so I’m counting her.
Created by Daron Nefcy, Star is chaotic energy in princess form. Magic wand, butterfly cheek marks, best friend named Marco. Iconic 2010s Disney character.
2Wander – Wander Over Yonder (2013-2016)
Wander is a small, orange, fuzzy alien who travels the galaxy with his Zbornak companion Sylvia, helping people, playing his banjo, and generally being the most relentlessly positive being in any cartoon.
Voiced by Jack McBrayer, Wander is what happens when you turn Kenneth from 30 Rock into a cosmic explorer. Massively underrated show.
1E.T. – E.T. the Animated Series (Never actually made)
Quick correction on the original article on this one: an “E.T. The Animated Series” was developed and pitched, but never actually made. E.T. mostly stays a film character. He still belongs on any cartoon alien list because his design and personality have influenced basically every “gentle alien” character that came after him.
If you want animated E.T., you’ll find him in shorts, commercials, and a few crossover bits, but no full series.
Why Aliens Work So Well in Cartoons
The big reason: Aliens let writers say things they couldn’t say with human characters. You can have a tiny green guy critique modern society. You can have a fuzzy creature from another planet teach kids about family. You can have a tentacled monster make jokes about politics. Aliens are a free pass for weird, smart, and dangerous storytelling.
That’s why almost every animated universe ends up with at least one alien character eventually. They’re flexible. They’re visually distinct. They can do anything.
Honorable Mentions
A few alien cartoon characters that almost made the cut:
- Lrrr, Ruler of Omicron Persei 8 from Futurama
- Pleakley and Jumba from Lilo & Stitch (covered separately)
- Yumi from Hi Hi Puffy AmiYumi (no, kidding, but you remembered the show, didn’t you?)
- Aang from Avatar — okay he’s not an alien, but he flies on a sky bison, close enough
- The Klingons from Star Trek: Lower Decks
- Megatron and the Transformers if you count robotic aliens
My pick for #1: Stitch. He’s the rare alien character who works for kids, adults, fans of action, fans of feelings, and people who just want a blue koala to be happy. Lifetime achievement.
Hot take: Marvin the Martian is the most influential alien on this list. Almost every “calm, polite, slightly menacing” alien character traces back to him. He’s been doing it since 1948 and he’s still relevant.
So, who’s your favorite alien cartoon character of all time, and did I miss anyone you think absolutely deserves a spot? I want to hear it, even if you’re going to fight me about Gazoo.
