Disclosed herein is a brake system for a fishing reel. The brake system includes a spool cover which is provided between a spool and a left cover, and a brake assembly which is provided between the spool and the spool cover. The spool cover has a cylindrical inner sidewall, a first brake collar which is provided on the inner surface of the sidewall, a circular protrusion which is provided on the central portion of the spool cover, and a second brake collar or one way ring which is provided on the circular protrusion. The brake assembly includes a brake housing, brake shoes, expansion springs, and a housing cover. The brake housing has inner seating depressions and outer seating depressions therein. The brake shoes are inserted into the inner seating depressions. The expansion springs are inserted into the inner seating depressions to elastically support the brake shoes. The housing cover is coupled to the outer surface of the brake housing to prevent the brake shoes and the expansion springs from being removed from the brake housing.