The former West Bromwich Albion defender had more recently been working as a professional development coach for the Baggies since the summer.
However, having played alongside Blackburn manager Michael Appleton at the Hawthorns, Moore admitted that he had no hesitation in joining his former teammate at Ewood Park.
"When the gaffer asked me to come up here and be part of his staff, I was really excited and I can't wait to get started," Moore told the club's official website.
"We were teammates together at West Bromwich Albion and after sustaining an injury early in his career, the gaffer started to pick up his coaching credentials and setting the foundations to be a really top coach and manager now.
"He's someone that I've believed in from day one. He's got excellent tactical awareness for the game and his all-round manner is perfect for the football club. I've seen it first hand and I'm just really looking forward to working alongside him and the rest of the staff and bringing some good times back here to Blackburn Rovers."