A fishing reel power device is characterized by a variable speed motor and adapter combination which can be used with a conventional fishing reel for automatically winding the same. The adapter includes either recesses for receiving the handle and counterweight of a fishing reel crank and/or a pair of projections which engage the crank. A further recess in the end of the adapter receives a nut on the reel to align the device with the reel. The motor is activated by a switch to rotate the adapter and thus the reel crank. The adapter is designed to retain the engaged portions of the reel with a gripping force which increases as the load on the motor increases. Once winding is complete, the adapter is easily disengaged from the reel so that the reel is available for manual operation.