The seven-year-old has received rave reviews for her performance as Moonee in the movie, and was rewarded with a Best Young Actor trophy on Thursday night.
Tearfully taking to the stage, she said: “Wow, this is such a big honour.
“All the nominees are great, you guys are awesome… we should go and get ice cream after this.”
As the gathered audience watched on supportively, she continued: “Al my voters, you guys are awesome, thank you so much.
“God, I would like to thank you for this wonderful opportunity… And I would like to thank Sean [Baker, director] for giving me this opportunity to be his Moonee, and the cast and crew for giving the support, my family and my team.
“And I would like to dedicate this to all the Hailees and Moonees out there, you need to go out there and help.”
The Florida Project is set in the area around the DisneyWorld Resort in US state, following a mother and daughter who try to make the best out of life despite very limited resources.
Willem Defoe co-stars, and is picking up Best Supporting Actor nominations at several ceremonies.
The Florida Project has been surprisingly absent from many Best Picture fields, despite huge acclaim.
Baker’s previous film was Tangerine, which follows a transgender sex worker and was shot entirely on iPhone 5s devices.
The Florida Project is still showing at some cinemas nationwide.