Zell, whose took over the company two years ago, will stay on as chairman.
"They've already seen his stamp on the company," said Crain's Chicago Business reporter Ann Saphir. "He's brought in a lot of the executives, he's made a lot of decisions about consolidation, about the staff layoff.
Zell’s replacement comes exactly one year after the company filed for Chapter 11 bankruptcy protection as it was being crushed by a $13 billion debt.
"During the last two years, we’ve achieved a seismic shift in Tribune’s focus and culture—we’re moving in the right direction and into the new year with energy and optimism," Zell said in an internal message to Tribune staff.
To reverse its tough economic situation, the company recently sold the Chicago Cubs to the Ricketts family and has been looking to sell other valuable assets like the Tribune Tower on Michigan Ave.
"Sam Zell has been associated with the leverage buyout. He's called it a big mistake, a big miscalculation, so for him to step back from that a little bit, I think is completely natural," Saphir said.