Bialik will share hosting duties with the show's executive producer Mike Richards, producers announced Wednesday, after a prolonged search for Trebek's successors.
Richards will helm daily syndicated episodes when the show embarks on season 38 next month, while Bialik will take charge of special primetime events and spin-offs, including a new collegiate championship, Sony Pictures Television said.
The 45-year-old Bialik, who played geeky neuroscientist Amy Farrah Fowler on the hugely successful "The Big Bang Theory" -- and has her own PhD in the same field -- said she was "thrilled" with the news.
"What started out with my 15-year-old repeating a rumor from Instagram that I should guest host the show has turned into one of the most exciting and surreal opportunities of my life!" she said.
"Jeopardy!" has been running in one form or another on US television since 1964, scooping up a bevy of awards over the decades.
In a twist on the quiz show format, contestants are given answers, to which they must provide the question.
Trebek, a Canadian by birth, became synonymous with the program over his 36 years as host, and his death after a battle with pancreatic cancer provoked an outpouring of emotion from contestants, fans and .
Finding a replacement was always going to be a challenge for producers, who ran through a series of guest presenters this year, including Bialik and Richards, in the wake of Trebek's death in November 2020.
That group included celebrity journalists Katie Couric, Anderson Cooper and George Stephanopoulos, as well as Green Bay Packers quarterback Aaron Rodgers and sports commentator Joe Buck.
The final decision came after months of speculation about who would take charge -- and months of heated debate among the show's most loyal fans.
The appointment of Richards, 46, has sparked controversy in some circles, not least because of renewed media attention on employment discrimination lawsuits filed by women when he was executive producer of "The Price is Right."
In an internal memo obtained by CNN, Richards defended himself, saying "the way in which my comments and actions have been characterized in these complaints does not reflect the reality of who I am or how we worked together on 'The Price is Right'."
