A turning control unit for controlling a marine propulsion machine which includes a rotatably driven propeller and is turnably mounted to a marine vessel for setting a propulsive direction, the unit comprising: an operating handle arranged to output a handle signal indicative of a turning position of the marine propulsion machine by setting the turning position thereof; a sensor arranged to detect the turning position of the marine propulsion machine and output a feedback signal; control means arranged to calculate a deviation between the handle signal outputted from the operating handle and the feedback signal outputted from the sensor, the control means further arranged to calculate a motor-speed reading according to the deviation, and simultaneously transmit the motor-speed reading as the same digital signal to a plurality of objects via digital communications; a plurality of AC servo amplifiers (A1, A2) arranged to each receive the motor-speed reading simultaneously transmitted as the same digital signal from the control means via the digital communications and output a motor speed command value according to the motor-speed reading; a plurality of AC servo motors each of which are arranged to be driven in response to the motor speed command value from each of the AC servo amplifiers (A1, A2) so as to turn the marine propulsion machine; characterized in that each AC servo amplifier (A1, A2) includes load calculating means for calculating a load amount from a value of current through the AC servo motor; wherein each AC servo amplifier (A1, A2) is arranged to calculate and output the motor speed command value by correcting the motor-speed reading transmitted from the control means according to a load amount of the corresponding AC servo motor; wherein each AC servo amplifier (A1, A2) is arranged to perform a calculation for reducing the motor speed command value according to the load amount when the load of the AC servo motor is characteristic of power running; and wherein each AC servo amplifier (A1, A2) is arranged to perform a calculation for increasing the motor speed command value according to the load amount when the load of the AC servo motor is characteristic of regenerative running. an operating handle arranged to output a handle signal indicative of a turning position of the marine propulsion machine by setting the turning position thereof; a sensor arranged to detect the turning position of the marine propulsion machine and output a feedback signal; control means arranged to calculate a deviation between the handle signal outputted from the operating handle and the feedback signal outputted from the sensor, the control means further arranged to calculate a motor-speed reading according to the deviation, and simultaneously transmit the motor-speed reading as the same digital signal to a plurality of objects via digital communications; a plurality of AC servo amplifiers (A1, A2) arranged to each receive the motor-speed reading simultaneously transmitted as the same digital signal from the control means via the digital communications and output a motor speed command value according to the motor-speed reading; a plurality of AC servo motors each of which are arranged to be driven in response to the motor speed command value from each of the AC servo amplifiers (A1, A2) so as to turn the marine propulsion machine; characterized in that each AC servo amplifier (A1, A2) includes load calculating means for calculating a load amount from a value of current through the AC servo motor; wherein each AC servo amplifier (A1, A2) is arranged to calculate and output the motor speed command value by correcting the motor-speed reading transmitted from the control means according to a load amount of the corresponding AC servo motor; wherein each AC servo amplifier (A1, A2) is arranged to perform a calculation for reducing the motor speed command value according to the load amount when the load of the AC servo motor is characteristic of power running; and wherein each AC servo amplifier (A1, A2) is arranged to perform a calculation for increasing the motor speed command value according to the load amount when the load of the AC servo motor is characteristic of regenerative running.