Madonna drew international attention by saying during an August concert in Bucharest on her "Sticky & Sweet"' tour that widespread discrimination against East Europe's Gypsies, also known as Roma, should end.
Thousands of fans responded by booing her.
"Madonna's very mild comment regarding equality shone a spotlight on a common European attitude toward Gypsies," Leslie Hawke, president of Ovidiu Rom, told The Associated Press. "We're thrilled to have her donation because she is such an icon of innovation and vigor and 'can do' spirit."
Hawke's son, actor Ethan Hawke, will attend the ball and speak to guests.
Guests at the ball will make donations to win raffle tickets for the auction of donated prizes. This year's items also will include a gold chain provided by actress Vanessa Redgrave.