An operator control system for a boat, where an outboard motor includes a throttle actuator that controls throttle opening of the engine, a shift actuator that controls a shift position to be put into one of neutral, drive, and reverse positions, and an engine control unit that controls the engine. An operation input portion, to control propulsion of the outboard motor and an operation quantity computation portion, that computes control command values including a start and a stop, the throttle opening, and the shift position of the outboard motor by detecting a steering state of a boat driver at the steering seat, are mounted on an operator station. The operation quantity computation portion transmits the control command values to the outboard motor via a communication portion, and the outboard motor performs control of the start and the stop, the throttle opening, and the shift position of the engine according to the control command values received.