An outboard motor control system can have a first PTT switch and a second PTT switch in a first steering station and in a second steering station respectively, and a third PTT switch in a location outside of a boat hull. Operation instruction given by each PTT switch can be input to a first microcomputer of a first ECU. The first microcomputer can determine if the inputted operation instruction is to be sent to the outboard motor, based on which PTT switch the operation instruction came from, whether the main switch is ON or OFF, and which steering station has precedence in boat control.