The "How I Met Your Mother" star and stage veteran will return to Manhattan's Beacon Theatre for the ceremony honoring Broadway's best on June 10.
In a statement, the Harris said he was thrilled to host again. "Not only will I be shining a spotlight on the best that Broadway has to offer, but hopefully I'll score some free house seats to a show - or five!"
Harris hosted the Tony's last year and in 2009 - the same year he hosted the Emmy Awards. He will also serve as a producer of the award show.
The 38-year-old actor has starred in three Broadway productions, including "Assassins," "Proof," opposite Anne Heche, and as the exuberant master of ceremonies in "Cabaret."
The Associated Press contributed to this report.