A reciprocating mechanism of a fishing reel is equipped with a worm shaft (5) including intersecting spiral grooves (5a) and an engagement pin (7), and a torque limiting mechanism (10). The engagement pin (7) engages the spiral grooves (5a). The torque limiting mechanism (10) limits the rotational drive force which rotates the worm shaft (5). At least a portion of the worm shaft (5) is made of synthetic resin. A fishing reel comprises such a reciprocating mechanism, a reel body (1), a handle (2; 102) rotatably disposed on the reel body (1), and a spool (4; 104) configured to have a fishing line wound thereon by rotation of the handle (2; 102); wherein said reel is a dual-bearing reel (100) having a level wind mechanism (50), or a spinning reel (200) having an oscillating mechanism (150).