Boyes was set to become an unrestricted free agent in July. His new deal is worth $5.25 million for the duration, according to several sources.
"We are pleased to have Brad back for the next two seasons," said Panthers GM Dale Tallon. "He has played an important role in our club's offense this year, leading our team in goals, while also performing well in shootouts. We look forward to his continued contributions to our organization."
In his first season with the club, Boyes leads the club with 17 goals and is tied for second with 28 points.
Since breaking into the NHL in San Jose during the 2003-04 season, the 31- year-old has picked up 185 goals and 250 assists in 666 regular-season appearances for San Jose, Boston, St. Louis, Buffalo, the Islanders and Florida.