I don't know :/

They both are equal in this regard. I wish there was an option for equally stubborn.

Gee, let me think...

I think that if Belle was as stubborn as Ariel, she'd always be angry at the beast.

So it's better for Ariel to get tagged with still another negative quality...? Whatever. This site is hopeless.

Belle stays angry and stubborn at the beast until he literally gives her his library. Belle is capable of holding a grudge. Belle and Ariel are both equally stubborn in my book.

Ahaha, yeah she is XD

8804: I don't think that's fair because stubbornness IS one of Ariel's most prominent characteristics. She's even called "head-strong" in the film. The entire story hinges on her pursuing the human world (sunken ships, the surface, Eric's heart, and then flat out becoming human) despite everyone telling her not to, and doing what she wants despite being warned of the dangers.

King Triton: Have you lost your senses completely? He's a human, you're a mermaid!
Ariel (glares in defiance): I don't care.

Later.

Sebastian: Ariel, what are you doing with this riff-raff?
Ariel (sticks up her nose): I'm going to see Ursula.
Sebastian (gasps): Ariel, no! She's a demon! She's a monster!
Ariel (glares): Why don't you go tell my father? You're good at that! (Shakes him off and swims away)

Belle can be stubborn too, but it's not one of her primary characteristics, it doesn't crop up as often, the story doesn't exactly center around her doing what she wants despite being warned not to, and the few times it does it's done to save her father's life (like trading her life for his despite his protests), or shake off an abusive controller like the Beast or Gaston. (Refusing dinner, marriage, etc.)

Both.

I mean, anyone who is determined is stubborn. Ariel's stubborness more stems out of her passions, but Belle is more stubborn up front. Stubborn isn't necessarily a bad quality at all.