The 25-year-old has signed a four-year contract and joins the club for an undisclosed fee from Hull City.
“A lot of things attracted me to Sunderland, the facilities, the stadium, the fan base,” Turner told the club’s official website.
“But a big factor was the manager. Steve Bruce is a proven manager in my position as a player and hopefully he can add to my game.
“He has a real pedigree and did a great job at Wigan.
“Now he’s come to the Stadium of Light and brought in some exciting players. I’m delighted to join that group.
“I’m over the moon to be here and get everything tied up. As soon as I knew of their interest there was only one place I wanted to go.
“With the deadline coming up it all happened quite quickly after I found out Sunderland were interested. I am pleased to be here.
“I have played at the Stadium of Light two or three times and it is an unbelievable place with a great atmosphere. It is one of my favourites.
“The signings which have already been made show Sunderland want to move in the right direction and I want to be part of that.”