Duclair's deal is worth $1.7 million, according to TSN's Pierre LeBrun.
The 25-year-old became an unrestricted free agent in October after the Ottawa Senators declined to give him a qualifying offer.
"Anthony is a dynamic and highly skilled player who is capable of being a dependable offensive contributor for our team" Panthers general manager BIll Zito said. "He possesses tremendous speed and goal-scoring ability and earned an opportunity to be named an NHL All-Star last season. We're excited to welcome Anthony and look forward to what he can add to our team."
Duclair notched a career-high 23 goals while adding 17 assists through 66 games with the Senators in 2019-20.
The Panthers needed another left-winger after seemingly moving on from sharpshooter Mike Hoffman this offseason, and they'll likely use Duclair in a top-six role in an attempt to replace some of Hoffman's offense.