The studio crowd broke into raucous applause when current host Drew Carey was announced at the start of the show, and Barker - who hosted the show from 1972 to 2007 - came out instead.
"I have never had a welcome like that," the 91-year-old told the audience, thanking them profusely. "I'm here because I was selected by The Price Is Right to be their April fool."
Barker went on to host the first round of the show - and made one lucky contestant's day before Carey took over. Check out the clip below:
(Full disclosure: TVGuide.com is owned by CBS.)