The Manchester City youngster has signed for the full season on loan.
He will be hoping to assist Rovers as they attempt to gain promotion from the Championship.
At 21, Adarabioyo is an intimidating defender with his 6ft 5in frame.
"We've been working on this deal for a good few weeks now and we're delighted he's here," Mowbray said to the club's official website after the move was completed.
"He's still a young boy, but the positive for me is that it's his second season-long loan having spent the last campaign at West Bromwich Albion.
"I think he grew into their season and we'll hopefully get the benefit of a confident and assured young guy who has amazing physical attributes.
"He's 6ft 5in, he's fast, mobile and good on the ball, just as you'd expect coming from a club like Manchester City."