Slime Princess looks just as she sounds, like a glob of slime. The majority of her body is dull lime-green color, but she also has a yellow center. She has two arms, that when not being used may disappear back into her body. She wears a tiara similar to that of Princess Bubblegum, only the gem in the center is green, while Princess Bubblegum's is turquoise. when she has an egg in her it appears under her face in the her yellow center.
After Patience's mega-spell, Slime Princess grew in size, but still retains almost all of her physical features, though she lost the ability to speak English.
In "Princess Day," it was revealed that she has the ability to pop out eggs from her body and trades them with other kingdoms. However, it was also revealed that she is an artisan and cannot just pop out eggs on command. It is unknown if other Slime People can do this as well.
Since "Elemental," Slime Princess has learned to spew slime out from her hands.
She was seen to be using the powers in "Jelly Beans Have Power."
In "Slime Central" she is shown in her elemental form. She was shown to turn others into slime elemental people. The slime elemental people were seen to be party animals and dancers. Slime Princess lost her memories while in her elemental form. While in her elemental form she would absorb others into her and they would appears to be vanished (or dead). In "Skyhooks II," when Lumpy Space Princess fixed Ooo back to normal, everyone who was absorbed into her were revealed to be alive.
- Her tiara resembles Princess Bubblegum's, which has the ability to block the telepathic power of the Lich. It is unknown if Slime Princess' has a similar ability.
- She is Pendleton Ward's favorite princess because she has a "hot lady voice."
- She was once rescued from the Ghost Ship Vortex by Finn and Jake, shortly before the events of "The Eyes."
- She is one of the princesses that Ice King finds to be his favorite as shown in "Princess Monster Wife."
- However, his lyrics in "Oh, Bubblegum" indicate that he thinks she's just "alright."
- According to CN Latin America, she wishes to be the ambassador of the animal kingdom and she fears salt. The latter fact may stem from salt being able to kill snails and slugs, which produce slime.
- In her elemental form, her body resembles Jabba the Hutt's from the Star Wars franchise.
- "Ricardio the Heart Guy"
- "The Eyes"
- "Video Makers"
- "Princess Monster Wife"
- "Princess Potluck"
- "Bad Little Boy"
- "Princess Day"
- "The Music Hole" (pictured)
- "Jelly Beans Have Power"
- "Bespoken For" (flashback)
- "Skyhooks II"
- "Come Along With Me"