A spool brake device for a dual-bearing reel according to a first aspect of the present invention is a device configured to electrically brake a spool rotatably mounted to a reel unit of the dual-bearing reel for allowing a fishing line to be wound thereabout. The spool brake device includes a spool brake unit including a magnet configured to rotate in conjunction with rotation of the spool, and a coil configured opposite to the magnet to generate electric current with rotation of the magnet, a tension detecting unit configured to detect and measure tension on the fishing line, and a spool control unit configured to control the spool brake unit by analog-controlling electric current flowing through the coil on the basis of how large the tension is.
