The left-hander, who retired from international cricket in January this year, will play alongside Australia captain Michael Clarke for Thunder in this year's BBL. Hussey has left the Perth Scorchers and moved to Thunder. Clarke will lead the side while Hussey will captain when the right-hander is not available.
The 38-year-old has been a successful opener for Indian Premier Leauge (IPL) franchise Chennai Super Kings. He was involved with the team in this year's edition too.
"I'm extremely excited about joining the Sydney Thunder and having the opportunity to be part of a young, energetic side that will represent the West of Sydney with pride." Hussey was quoted as saying on the team's website.
"The team and the area have enormous potential and I hope that I can bring my experience to help get the best out of the side and develop the talented playing group that we have. It was not an easy decision to leave the Scorchers, but the challenge of helping a young team grow was one I couldn't pass on.
"I look forward to working closely with Coach Chandika and Michael Clarke to make sure that the squad are ready to go once the season starts. It will be exciting to play at ANZ Stadium next season and we look forward to playing positive cricket and making the members and fans proud," he added.
Clarke said Hussey is an outstanding cricketer and a great team man.
"The signing of Mike Hussey is great news for Thunder members and fans. Mike is an outstanding cricketer and a great team man and the experience and abilities as a player that Mike will bring, will be of enormous benefit to the squad of players that we have. I look forward to working closely with Mike when I have the opportunity to be part of the Thunder this season," Clarke said.
This year's BBL commences on December 20.