The comedian's return to the show that he began to host in 1999 will be temporary – until the end of the elections.
He will also only host a short portion of the show on Mondays and will otherwise be overseeing things from behind the scenes as an executive producer.
“Who better to comment on this election than someone who truly understands two ageing men past their prime?” Stewart told CBS.
The show, which airs on Comedy Central, has been without a main host since Trevor Noah departed in 2022.
Stewart's blend of iconoclasm and straight-talking led The New York Times to ask in 2008 if he was the “most trusted man in America”.
During his tenure, the show became famous for its no-holds-barred commentary on politics and major issues, foreign and domestic.
Since he left the show in 2015 – right before the election that resulted in a win for Donald Trump – Stewart has spent his time advocating for US veterans and 9/11 first responders, as well as hosting a show on Apple TV.
He has also continued to weigh in on political issues, including the Israel-Gaza war.
In late October, alongside a number of other celebrities, Stewart wrote to President Joe Biden and called for an urgent ceasefire in Gaza.
“We urge your administration, and all world leaders, to honour all of the lives in the Holy Land and call for and facilitate a ceasefire without delay – an end to the bombing of Gaza, and the safe release of hostages,” the celebrities wrote.
“We refuse to tell future generations the story of our silence, that we stood by and did nothing.”