Wolves are chasing the centre-back, who is rated at ?4million, as boss Mick McCarthy reshapes his squad ahead of the forthcoming season.
O'Hara played in the same England team as Mills at youth level and reckons the 24-year-old would be a good acquisition for Wolves.
"I played with him a few times for the England age group teams and I think he's a fantastic player," said O'Hara.
"He's a good lad and he'll fit right into our squad. It's important to fit in straight away with the boys, and he'll have no problems.
"He had a great season in the Championship with Reading and if we can get him then that would be great."
Source: Team Talk
Source: Team Talk