Albion confirmed the news late on Thursday night, stating that everyone at the club was 'deeply saddened' by the news.
Miller made more than 100 combined appearances for the Baggies, having two separate loan spell at The Hawthorns from boyhood club Arsenal and Middlesbrough, before joining on a permanent deal in 1997.
He played for the club until 2000, before he signed for Blackburn Rovers. He also had a loan spell with Birmingham City in the 1991/92 season.
Tributes were paid to the former shot-stopper, with ex-Arsenal teammate Lee Dixon one of many to share his devastation at the news.
"Devastated to hear the news that our team mate Alan Miller has passed away."
"He was one of life's good guys. What a man. Heart of gold. RIP my friend." he tweeted.
Alan Smith, former Arsenal striker also paid his respects following the news.
"A great roommate, teammate and friend. Rest in Peace Maxi." he tweeted.
Meanwhile, former Baggies goalkeeper Ben Foster hailed Miller as a 'top class human being'.
"I didn’t know him, but was always told he was a a brilliant goalkeeper and a baggies legend. More importantly tho [sic], he was apparently a top class human being. RIP Alan Miller."