Mariota participated in the event Saturday at Nissan Stadium.
The Titans posted videos of the quarterback playing catch with children on their home field. Titans coach Mike Vrabel was also in attendance for the Music City Blitz.
"It gives the experience for your average day couch potato, average Joe to come out and play and be a pro," Special Olympics of Tennessee president Adam Germek said in a Twitter video from the Titans.
The children participated in flag football at Nissan Stadium.
"I just like seeing their faces light up," Mariota said in a video for the Titans. "I enjoy being around them. I think they've got such a great perspective on life and they are always so happy."
"I heard one of our athletes say this is the best day of his life," Germek said.