For the last three seasons, he has also held the position of forwards coach with the Ospreys Academy sides, working closely with the Under 16 and Under 18 age groups.
Millward said today: "I've been coaching with the Ospreys Academy for the last three years and this just seems a natural progression for my coaching career. It's a move that will benefit all parties, it will help me develop further as a coach and also, I can provide a good link between the region and Bridgend.
"I'm going to be busy next season with training everyday and playing for the Ospreys when required, as well as training at Bridgend two nights a week and matches on a Saturday but I'm looking forward to the challenge, and taking the next step forward as a coach."
Bridgend Director David Rees said: "Andrew being an attached coach is seen as a further sign of the Ospreys commitment to Bridgend."