The former Trump White House Communications Director had announced her retirement in February, one day after testifying before Congress she had lied for the president.
Media mogul Rupert Murdoch will retain ownership of Fox, the new spin-off company that includes the cable news network.
While not a direct swap of assets, the tradeoff between the White House and Fox has a certain air of symmetry about it.
Hicks' hiring was announced Monday by Viet Dinh, chief legal and policy officer.
During the nine-hour interview, Ms Hicks acknowledged that she had occasionally told "white lies" for Mr Trump, but she said she had not lied about anything relevant to the Russian Federation investigation.
Before the deal closes, expected next year, Fox will separate the Fox Broadcasting network and stations, including Fox News Channel and Fox Business Network, into a newly listed company.
Hope Hicks has landed a new job. It seems to deepen the relationship between Fox News and the White House, where former Fox News executive Bill Shine is the communications director. O'Brien was previously chief of staff for Democrats Joe Biden and Robert Menendez. Others in the Trump administration also hail from the Fox News family, including Heather Nauert, a Fox News host-turned State Department press secretary.
"So happy for my friend", she tweeted. He's a longtime Washington hand who most recently worked at General Electric. "They are beyond lucky to have you and the East Coast misses you already".