A fishing reel with improved transmission efficiency is disclosed to include a shaft mounted in a casing, a spool sleeved onto the shaft, a brake pad mounted at one side of the spool, two disks mounted at two sides of the brake pad and rotatable by an external force, and a support set provided between the spool and the shaft. Thus, when the shaft is moved axially to a predetermined position, the shaft exerts a pressure to one disk and the spool via the support set, causing the brake pad to be clamped by the two disks. Therefore, the fishing reel is provided with excellent power transmission efficiency and strong spool braking force.