Producers of the game show confirm Trebek took part in Tuesday's tapings.
Trebek, 78, is battling stage 4 pancreatic cancer, but said he plans to continue working while getting treatment.
"Normally the prognosis for this is not very encouraging, but I'm going to fight this and I'm going to keep working," Trebek said in a video message released on "Jeopardy!" social media accounts on March 6.
In response to fans' reactions, the "Jeopardy!" Twitter account posted, "The outpouring of good wishes and support in response to Alex's recent health news has been humbling and overwhelming. Please know that your messages are being conveyed to him and are deeply appreciated. From everyone at Jeopardy! - thank you."
"Jeopardy!" usually just tapes two days a week and records multiple episodes in a day.
Trebek has served as the face of the game show since it made its debut in daytime syndication in 1984. With nearly 8,000 episodes under his belt, he holds the Guinness World Record for Most Game Show Episodes Hosted by the Same Presenter.