SANTA BARBARA, CALIF. -- The White House, which has struggled to find a center for the 3,000 to 5,000 journalists expected to cover the Washington summit next month, yesterday said that the media will work out of the J.W. Marriott Hotel.

The administration's first choice, George Washington University's athletic arena, was rejected by the school's president because it would disrupt classes and recreational time for students and faculty. And other hotels had said they would be unable to cancel reservations on such short notice.

But the hotel -- owned by the Marriott family, which is prominent in Republican circles -- persuaded other organizations to give up their reservations to accommodate an estimated 3,000 to 5,000 journalists expected to cover the Dec. 8-10 summit between President Reagan and Soviet leader Mikhail Gorbachev.

Both print and broadcast reporters will work in the hotel's large ballroom, which is expected to be the site of a Gorbachev news conference.

An auxiliary news room for additional journalists and for technical facilities will be set up in the Commerce Department auditorium across the street from the Marriott, at 1331 Pennsylvania Ave. NW. Both are two blocks of the White House, where all the meetings will be held.

The media center will be ready Dec. 7, the official said.

White House spokesman Marlin Fitzwater lashed out at George Washington University's refusal to house the media, saying it had given itself "a black eye."