ELECTRIC POWER STEERING DEVICE

PROBLEM TO BE SOLVED: To provide an electric power steering device in which a control unit is attached to a gearbox attachment surface of a reduction gearbox without disposing a space therebetween.SOLUTION: A notch part 28a allowing a plurality of external connection terminals 15c-15f to pass through is formed in a cover plate part 28 of a cover of the control unit opposed to the gearbox attachment surface 20b of the reduction gearbox 4. An attachment part 35 of a seal member 33 grips a peripheral edge 34 of the notch part 28a. A skirt part 36 of the seal member 33 being continuous from the attachment part 35 adheres to the gearbox attachment surface 20b while closing the space occurred between the cover plate part 28 and the gearbox attachment surface 20b.