To allow plural AC servo motors of an electric turning control unit to share load equally.
A turning control unit 2 for controlling a freely turnable marine propulsion machine includes: a turning control board 7 which calculates a digital motor-speed reading from a deviation between a signal from a sensor 6 for detecting a turning position of the marine propulsion machine and a handle signal; and a plurality of AC servo amplifiers A1, A2 which drive AC servo motors M1, M2 by receiving the motor-speed reading from the turning control board and outputting a motor speed command value. Each amplifier is adapted to reduce the motor speed command value according to a load amount when the motor performs power running, to increase the motor speed command value according to the load amount when the motor performs regenerative running, and to make no correction when the load amount of the motor is equal to or less than a fixed value. The respective loads on the plural AC servo motors can be dispersed to a uniform value.