The team announced the move on Sunday.
Assistant coaches Martin Raymond and Dan Lacroix will share coaching responsibilities for Sunday night's game at Winnipeg.
Lightning general manager Steve Yzerman said in a statement that "Guy has poured his heart and soul into the Lightning organization for these past three years and we appreciate all the work he has done."
However, he said "ultimately I am not satisfied with the direction we are heading and I believe making a change today is in the best interest of our franchise."
Tampa Bay is next to last in the Eastern Conference with a 13-17-1 record.