With 73 games in the navy blue already to his name, Barbarouses re-joins the club for a further two seasons.
Barbarouses exited Wellington with another year remaining on his contract, after requesting a release for personal reasons.
The 27-year-old joins Socceroo Rhys Williams and young defender Thomas Deng as additions to coach Kevin Muscat’s squad ahead of the 2017/18 A-League season.
"We’re extremely happy to have secured Kosta’s services again," Muscat said.
"Kosta is a player who really complements the way we like to play and to be able to sign him for the next two years is a big boost so early in the recruiting process.
"There’s no doubt in my mind that his best years are still ahead of him, so he’ll be an important player as we navigate our way through a busy campaign that also includes AFC Champions League.
"I'm sure our fans will be thrilled with this news as the build up to next season continues."
Barbarouses shared his coach's excitement about returning to Victory.
"This really couldn't have worked out any better for me," he said.
"I've enjoyed some fantastic times at Melbourne Victory in the past and when the opportunity arose to return, I jumped at it.
"I'd also like to thank Wellington Phoenix for understanding my situation and the professional way they handled it. I certainly wish them all the best moving forward."
Barbarouses is currently in camp with New Zealand and will be part of the All Whites Confederations Cup campaign.
A date for his arrival to pre-season training is yet to be determined.