A spool assembly for a dual bearing reel includes a tubular bobbin, first and second flange portions, first and second annular portions, and first and second fishing line entry prevention portions. The first and second flange portions project radially outward from opposite ends of the bobbin. Inner peripheries of the first and second annular portions cover the first and second flange portions. The first and second fishing line entry prevention portions project from outer peripheries of the first second flange portions. The first and second fishing line entry prevention portions are provided across a slight gap between tip portions of the first and second annular portions. The first and second fishing line entry prevention portions prevent fishing line from entering between the first flange portion and a first side plate and between the second flange portion and the second side plate.