The participants threw more than 100,000 balloons Saturday at the Pittsburgh Great American Water Balloon Fight, which was held at the Highmark Stadium.
Ian Rosenberger, a Survivor reality TV show contestant, began the event last year to benefit his charity, Team Tassy, the Pittsburgh Tribune-Review said.
Last year's fight raised $22,000 for Haiti to help with cleanup efforts from the 2010 earthquake that destroyed much of the country.
Organizers said they were hoping to double that amount this year.
Saturday's event began with a video of Haitians thanking the crowd, the Tribune-Review said.
"That makes it more real," said Jackie Freyer, 26, of Murrysville, who raised $200 with three friends for the effort. "Global poverty is an awful thing to go through. It's good to put a face to the cause."