A spool includes a tubular bobbin trunk, a pair of flanges and a boss member. The bobbin trunk has a peripheral surface extending along the axial direction of the spool so that a fishing line can be wound around the bobbin truck. The peripheral surface of the bobbin trunk includes thickened wall portions disposed on opposing sides of an axial center part of the bobbin trunk. The flanges are integrally formed with the peripheral surface of the bobbin trunk as a one-piece, unitary member. Each of the flanges extends substantially in a radially outward direction of the spool. The boss member is disposed between axial ends of the bobbin trunk and extends along the radial direction of the spool. The boss member includes a disc portion with a through-hole to receive a spool shaft. Each of the thickened wall portions has a thickness greater than other portions of the bobbin trunk.