The drag mechanism includes a friction disk, a cover member, a brake disk, and a drag adjusting mechanism. The friction disk is in a storage space of a first flange portion of a spool and has an engaging recess formed in an external circumferential surface. The cover member has a cylindrical portion that fits into an internal circumferential surface of the storage space, an engaging protrusion on a distal end surface of the cylindrical portion to engage with the engaging recess, and a protruding portion that mate closely with an end face of the first flange portion. The cover member is fixed to the first flange portion and covers the storage space from the outside. The brake disk is arranged in the storage space facing opposite the friction disk and constructed not to rotate in a line reel-out direction. The cam mechanism is designed to move the friction disk and the spool together along an axial direction of the spool with respect to the brake disk such that the friction disk is pressed against the brake disk.