"Save Dupree Studios," scheduled from 2 to 9 p.m., is also expected to include an interview with world-renowned artist Gene Marks, a writer specializing in small business for publications including Forbes, the New York Times and the Huffington Post.
The city has said that a supermarket would be built on the property.
"I want the community and the city of Philadelphia and all interested parties to come see what I have here. It's no mystery," Dupree said. "I want people to see what they plan to tear down through the eminent-domain laws. This is nothing more than a land seize."
Mayoral spokesman Mark McDonald wrote in an email yesterday: "We are in discussions with representatives of Mr. Dupree and are hopeful of reaching an agreement that meets everyone's needs. In the meantime, the case works its way through the courts."
The next hearing in the case is scheduled for April 23.
Inside the vast studio, visitors can see 5,000 works of art and tour parts of the studios where Dupree creates art, teaches classes and keeps space for studios that can also be used as bedrooms.
Painted on a wall outside Dupree's studio is a mural of a large hand bleeding at each fingertip. Below, it reads, "Hands off my business."
Various groups are helping to organize the open house, including the local chapter of the American Civil Liberties Union and the Virginia-based Institute for Justice, a nonprofit public-interest law firm specializing in private-property rights.
"We're really concerned because it's unconstitutional and unconscionable," said Melinda Haring, activism manager for the Institute for Justice, who is expected to speak at the event. "Eminent domain targets people least able to defend themselves. Minorities and the elderly are disproportionately affected by eminent domain."
In January, a coalition of several groups, including the state and local chapters of the ACLU, the Painted Bride Art Center, Americans for Prosperity: Pennsylvania, the Institute for Justice and others sent a petition to Mayor Nutter and City Council opposing the takeover.
Other victims of "eminent-domain abuse" will also be invited to attend the event, Haring said.
On Twitter: @ReginaMedina