A double-bearing reel which is readily disassembled and reassembled. The double-bearing reel is provided with a spool rotatably supported between side plates, the spool being rotatably geared to take-up driving mechanisms. A level winder unit is provided for guiding and winding a fishing line onto the spool in parallel. The level winder unit includes a worm shaft rotatably geared to the take-up driving mechanisms of the spool, a guide tube embracing the worm shaft and having a slit, and a fishing line guide reciprocating along the slit of the guide tube as the worm shaft rotates. A removal preventive member is provided for preventing the level winder unit from slipping off in cooperation with the side plates when the level winder unit is detachably installed in the mating openings formed in the respective side plates.