McManaman, 29, spent more than a decade in the Premier League and English Championship and will bolster Victory's attacking stocks -- led by Marco Rojas and Robbie Kruse -- as the four-time champions attempt to bounce back from a dire 2019-20 season.
"Callum is a very experienced player who has performed on the biggest stage in the world's toughest club competition, the English Premier League," Victory coach Grant Brebner said.
"He's a wonderful addition to our playing group.
"Callum works hard both ways... and at only 29 years of age has plenty of good football ahead of him.
"There's no question Callum is a very talented player but what he also brings is leadership and a hunger for success.
"He will play an important role in driving the standards of our playing group on and off the pitch."
McManaman has secured his visa and travel exemption and is expected to arrive in Melbourne in the coming weeks.
"This is a proud club with a huge supporter base and we all want to help get Victory back up the table," McManaman said.
"It's going to take plenty of hard work, but I can't wait to get started under Grant."