The 21-year-old has signed a three-year contract with the Latics and joins the club for an undisclosed fee from Chelsea.
“I think I needed to come to Wigan Athletic at this point in my career,” Di Santo told the club’s official website.
“Chelsea is a fantastic club but I didn’t have too many opportunities there, so I’m very happy to have made this move.
“At my age I need to be playing regular football so it’s an important move for me and I hope to earn a place in the team and then try my hardest to stay there.”
He added: “There were some other offers at the time but Wigan was the move I wanted.
“I wanted to stay in England, in the best league in the world and join a club that is moving in the right direction.
“So together with my family and friends I decided this was the right move for me.”
