He started his career at Stoke as a trainee before Ward, while Cheltenham manager, took him on loan in 2003 and signed him permanently a year later.
He joined Bristol City in 2007 where he made 74 appearances, scoring once.
Ward told the club's website: "He can play as a full-back, winger or wing-back.
"I signed him at Cheltenham for £50,000 and he went onto Bristol for £150,000 a couple of years later.
"He has played 60-odd games in the Championship and, although he has been unlucky with injuries, they've cleared up now and we've got a good player."
Wilson became Ward's second signing within 24 hours after Andy Bond joined from Barrow.
Source: BBC Sport
Source: BBC Sport