A spool brake device for a fishing reel includes a velocity detector, a spool controller and a spool brake. The velocity detector is configured to detect a rotational velocity of a spool. The spool controller includes an acceleration generator, an acceleration determiner and a brake time predictor. The accelerator generator is configured to generate time-series data of a rotational acceleration based on the rotational velocity. The acceleration determiner is configured to determine whether the rotational acceleration has satisfied a predetermined condition based on the time-series data of the rotational acceleration. The brake time predictor is configured to set a prediction starting time based on a point of time at which the rotational acceleration has satisfied the predetermined condition and to predict a brake starting time of the spool based on the prediction starting time. The spool brake is configured to start braking the spool at the brake starting time.
