"I'm thrilled to be heading to Perth," Miller said from Scotland.
"I have heard a lot of wonderful things about the City of Perth but football is the most important thing.
"Perth Glory is a proud club with a great history and I'm looking forward to the new challenge when I join Ian Ferguson and my new team mates."
In a stellar career to date, Miller has played for two of the biggest clubs in the United Kingdom and also had stints with Leeds United and Sunderland. Miller joins Perth Glory after spending the last two seasons in the Scottish Premier League with Hibernian.
"I'm delighted to have Liam on board," Perth Glory Coach Ian Ferguson said. "He is a quality player.
"Liam brings a lot of experience to the club and he's played at a number of top clubs.
"It's great to have a player of Liam's calibre at Perth Glory.
"Liam is a midfielder who gets forward and he'll help us become a more attacking team than last season," Ferguson added.
Miller, 30, made his international debut for the Republic of Ireland in 2004 against the Czech Republic and has played 21 games for The Boys in Green. Miller was also part of the Irish squad that won the UEFA U-17 Championship in 1998.
Miller is the ninth new player signed by Perth Glory for the 2011/12 season. He joins Danny Vukovic, Neil Young, Evan Berger, Dean Heffernan, Adam Hughes, Travis Dodd, Shane Smeltz and Jesse Makarounas as new faces for the coming season.