Abstract: A reel brake assembly for a magnetic recording/reading apparatus comprises a sub-deck slidably disposed on a main-deck in which a head drum is mounted, a reel table rotatably disposed in the sub-deck, for selectively driving a tape reel of a tape cassette, a brake unit pivotably disposed on the sub-deck, for selectively braking the reel table, and a cam gear rotated by a driving force of a driving motor, for moving the sub-deck to load and unload the sub-deck. The brake unit is selectively brought into contact with and separated from the reel table in relation to movement of the cam gear when the sub-deck is loaded and unloaded.