An electric power steering control device comprising: a motor configured to receive electrical power from a battery and output an assist force for assisting steering with a steering wheel; a battery voltage sensor configured to detect a voltage of the battery; a target value setting unit configured to set a gain target value (G*), which is a target value of a gain used to control the assist force output by the motor, on a basis of the voltage detected by the battery voltage sensor; a gain setting unit configured to set the gain on a basis of the gain target value (G*) set by the target value setting unit; a torque sensor configured to detect a steering torque applied by the steering wheel; and a control unit configured to control the assist force output by the motor on a basis of the gain set by the gain setting unit and the steering torque detected by the torque sensor, wherein the target value setting unit sets the gain target value (G*) to a predetermined usual value when the voltage detected by the battery voltage sensor is within a predetermined range of usual voltage, and sets the gain target value (G*) to a value below the usual value when the voltage is outside the range of the usual voltage; and wherein when the voltage detected by the battery voltage sensor is recovered from outside the range of the usual voltage to within the range of the usual voltage, the gain setting unit determines whether or not a ratio obtained by dividing a time-integrated value of the gain in a period from when the voltage goes outside the range of the usual voltage to when the voltage is recovered to within the range of the usual voltage by a time-integrated value of the gain when the gain in the period is the usual value is larger than a predetermined prescribed threshold (Rth), the gain setting unit setting the gain to immediately increase up to the gain target value (G*) when the ratio is determined to be larger than the prescribed threshold (Rth), and setting the gain to gradually increase up to the gain target value (G*) when the ratio is determined to be equal to or less than the prescribed threshold (Rth). a motor configured to receive electrical power from a battery and output an assist force for assisting steering with a steering wheel; a battery voltage sensor configured to detect a voltage of the battery; a target value setting unit configured to set a gain target value (G*), which is a target value of a gain used to control the assist force output by the motor, on a basis of the voltage detected by the battery voltage sensor; a gain setting unit configured to set the gain on a basis of the gain target value (G*) set by the target value setting unit; a torque sensor configured to detect a steering torque applied by the steering wheel; and a control unit configured to control the assist force output by the motor on a basis of the gain set by the gain setting unit and the steering torque detected by the torque sensor, wherein the target value setting unit sets the gain target value (G*) to a predetermined usual value when the voltage detected by the battery voltage sensor is within a predetermined range of usual voltage, and sets the gain target value (G*) to a value below the usual value when the voltage is outside the range of the usual voltage; and wherein when the voltage detected by the battery voltage sensor is recovered from outside the range of the usual voltage to within the range of the usual voltage, the gain setting unit determines whether or not a ratio obtained by dividing a time-integrated value of the gain in a period from when the voltage goes outside the range of the usual voltage to when the voltage is recovered to within the range of the usual voltage by a time-integrated value of the gain when the gain in the period is the usual value is larger than a predetermined prescribed threshold (Rth), the gain setting unit setting the gain to immediately increase up to the gain target value (G*) when the ratio is determined to be larger than the prescribed threshold (Rth), and setting the gain to gradually increase up to the gain target value (G*) when the ratio is determined to be equal to or less than the prescribed threshold (Rth).