The Socceroos central defender had been linked with a move to Crystal Palace, but he instead moves from Urawa Reds to Al Arabi in the Middle East
According to the league's website, the 24-year-old has signed a two-year deal with the Doha-based club, having impressed while training with the club on Monday.
Spiranovic arrives from J-League outfit Urawa Reds, for who he made only one appearance in the 2012 season, when he was sent off in the cup.
The former Nurnberg centre back made 25 appearances for the Reds in 2011 - 23 of them starts - but fell from favour this campaign.
"I want to thank the club and supporters from the bottom of my heart," Spiranovic told Urawa's website.
"I didn't just experience football; I experienced what it's like to be cheered on by fans with an extremely deep knowledge of the culture.
"I had a great time playing with Urawa and will never forget my experience here. I also want to thank my team-mates for their support and being able to play together with them. I wish Urawa Reds the best for the rest of the season."
Geelong-born Spiranovic has 14 Australia caps to his name and had been linked with English Championship club Crystal Palace before his move to Qatar.