The 22-year-old is starring as the mermaid in Disney's live-action version of the 1989 animated classic.
But after the trailer was unveiled she faced racist trolling from people questioning a Black star playing the character.
Speaking in a video on YouTube, Bailey said making the movie taught her to "believe in myself".
She also said that if she'd seen a Black Ariel when she was little it would have changed her "whole outlook on life".
"It was a big 'moral of the story' moment for me when I wrapped, because I dedicated so much time, blood, sweat, and tears into this work for this film," she said.
"In the process I learned so much about myself.
"I remember at the very, very beginning of filming I was way more timid than I was coming out of it.
"So I kind of felt like I grew with Ariel’s character in a way and that makes me really happy so yes, I think that was kind of the biggest takeaway for me is just to believe in myself and know that I’m worthy.’
Actor and singer Bailey also opened up all the talk about her role.
"Even still today like with all of the commentary and people’s opinions going on, it just reminds me to be number one grounded and grateful that I have this opportunity and the fact that it’s sparking such a discussion like this for all of us," she said.
"I mean, I know what it would’ve meant to me as a little girl to have been able to see a Black Ariel.
"When I was younger, if I would’ve seen that, it would have changed my whole outlook on life."
The star said the fact she was getting to do that was "really cool and unbelievable".
"The little girl inside of me is screaming and freaking out," she said.
Bailey also thanked fans for their support.
Watch: Rachel Zegler defends Halle Bailey's casting in The Little Mermaid in response to troll