Bob McKenzie of Canada's TSN first reported the hiring via Twitter on Tuesday.
Dineen will be formally introduced at BankAtlantic Center Wednesday at 3 p.m.
Dineen has been the coach of the AHL Portland Pirates since 2005. He broke into the league as a player with Hartford in 1984 and played for the Flyers, Hurricanes, Sens and Jackets.
After retiring, he worked under former Panthers coach Doug MacLean in Columbus.
Dineen replaces Pete DeBoer, who was fired the day following Florida's 1-0 win over Washington in the 2010-11 season finale. DeBoer spent three seasons behind the Florida bench and is signed through next season.