Shine resigned from Fox in May 2017, trailing the departure of Fox's ex-chairman, Roger Ailes, who resigned 10 months earlier after being accused of sexual harassment by a former host.
Less than a month before Shine resigned, Fox News host Bill O'Reilly was removed from the network amid his own allegations of sexual harassment. Both Ailes, who died less than a year after his departure, and O'Reilly denied the allegations.
Shine had been at Fox News since it launched more than 20 years ago. His departure had been strongly protested by Sean Hannity, the network's most popular host and pundit, who was reportedly longtime friends with Shine.
When rumors of Shine's ouster began to surface, Hannity said on Twitter that such a move would be "the total end of the FNC as we know it. Done."
Hannity, one of Trump's most loyal and outspoken defenders, reportedly has been described by White House advisors as a de facto member of the administration and even a "shadow" chief of staff.
Trump regularly touts Fox News, especially on social media, while bashing other media outlets as "fake news."
Shine was in talks with Trump administration officials to become the White House communications director, people familiar with the matter told CNBC in June. The post was vacated in March by Hope Hicks, the fourth to serve in the role under Trump.
Shine will accompany Trump aboard Air Force One on Thursday to a rally in Montana, Axios reported, where the president is expected to drum up support for Republican Senate candidate Matt Rosendale, as well as incumbent Rep. Greg Gianforte, in the midterm elections.
As Shine joins Trump's team, Joe Hagin, White House deputy chief of staff for operations, is preparing to resign.
Hagin had been credited as being a key player in the unprecedented summit last month between Trump and North Korean leader Kim Jong Un. He will step down Friday.