|Lumpy Space Prince|
|Name||Lumpy Space Prince|
|Species||Lumpy Space Person|
|Relatives|| Lumpy Space Queen (alternate father)|
Lumpy Space King (alternate mother)
|Introduced in||"Fionna and Cake"|
|Latest appearance||"The Prince Who Wanted Everything"|
|Voiced by|| Pendleton Ward ("Bad Little Boy"), ("The Prince Who Wanted Everything")|
Peter Serafinowicz ("The Prince Who Wanted Everything")
Lumpy Space Prince is the gender-swapped version of Lumpy Space Princess. He appeared in the season three episode "Fionna and Cake" and the season five episode "Bad Little Boy." In "Fionna and Cake," he made a cameo appearance, shown drinking from a blue cup. His second appearance was in "Bad Little Boy," where he was hosting a party. His third and first major appearance was in "The Prince Who Wanted Everything".
AppearanceLumpy Space Prince appears identical to Lumpy Space Princess, except with a mustache and a darker shade of purple. Like Lumpy Space Princess, he does not have a crown, but the star on his forehead probably indicates his position of royalty. His "Handsome Face" will allow any female who looks at him to become entranced. He does not use his power intentionally, for he is looking for someone exactly like him, such as Lumpy Space Princess.
- Not counting a technicality with Neptr, the only princes shown in the series are Lumpy Space Prince, Prince Gumball, Muscle Prince, Prince Huge, the Box Prince, Turtle Prince and Flame Prince.
- Lumpy Space Prince's voice is almost identical to Lumpy Space Princess', as both of them are voiced by Pendleton Ward.
- In "The Prince Who Wanted Everything", he became voiced by Peter Serafinowciz due to Lumpy Space Princess preventing Ice King from using her voice for him; this voice had a British accent rather than a Valley Girl accent.
- Lumpy Space Prince appears in Adventure Time Battle Party as an alternate outfit for Lumpy Space Princess.
- Interestingly, choosing the Lumpy Space Prince outfit will not actually change Lumpy Space Princess's in-game appearance. Instead, it will only change her voice.