Co-creator Carter Bays confirmed to TV Guide that Trebek will feature in the show's Christmas special, titled 'False Positive'.
"It's our twisted version of A Christmas Carol-type story," he revealed. "We see what it takes to get people back on track and start leading the life they're supposed to be leading."
Trebek has hosted quiz show Jeopardy! since 1984, and has also featured in episodes of Seinfeld and The X-Files.
How I Met Your Mother continues on Mondays at 8/7c on CBS.