"Rex knows how to manage a global enterprise, which is crucial to running a successful State Department, and his relationships with leaders all over the world are second to none," Trump said in a statement.
"I can think of no one more prepared and no one more dedicated to serve as secretary of state at this critical time in our history," he continued.
If confirmed by the Senate, Tillerson, who has spent his entire career at the oil company, would be the first secretary of state without any government or military experience in U.S. history. Trump met twice with Tillerson in person before his selection, after weeks of meetings with other contenders such as Mitt Romney, Gen. David Petraeus and Sen. Bob Corker, R-Tenn.
Tillerson emerged as a late contender for the job as the nation's top diplomat.
A supporter of free trade, he has a professional relationship with Russian President Vladimir Putin dating back to the 1990s. In 2011, ExxonMobil signed an agreement with Rosneft, an energy company majority-owned by the Russian government, to drill for oil in the Arctic.
That relationship was expanded in 2013, but the oil company started winding it down in 2014 after Russia annexed Crimea, which prompted U.S. sanctions. In 2013, Tillerson received the Order of Friendship award from the Russian leader.
Already, a number of Republican senators have expressed concerns about Tillerson's relationship with Russia, which could pose a challenge for his confirmation in committee votes and on the Senate floor.