Unlike many other inhabitants of Planet 51, Grawl is above average height, with broad shoulders and athletic, and muscular build. Source claims the exact height being 1,65 m. He is green skinned, has two antennas, four fingers and toes, and has brown eyes. He has short, slick back green (with a slightly different hue than his skin) hair that sometimes become messy when he is yelling. Fitting in his rank, Grawl wears a brown military coat, decorated with military emblems and badges, and has a belt, with a firearm holster for his pistol. Underneath, he wears a white shirt with a black tie and button. In some scenes, he can be seen with green-tinted sunglasses, either in his hands or on his snout, that block out harsh blue UV-light.

Lem is a lightly green-skinned alien, with a relatively stocky build, average height for his species (1,31 m ; according to source) and has two antennas. He is considered not to be bad looking, as he self-claims. He has short, green with yellowish ombre colored slick-back, and green eyes. Like the rest of his male's species, he does not wear pants. However, he wears a white t-shirt, and a red and yellow collar shirt.

Neera is an alien with green skin, emerald green eyes, and floppy, pointed ears. She has yellow head-tendrils for hair, a pair of stubby yellow antennas, and no nose. She wears a white shirt, a light purple skirt, a headband, and a string necklace with a white gem.

Skiff is an alien with green skin, green eyes, antennas on his head, thin arms and legs, and stretched-out limbs. He has a skinny build and a geeky, expressive look