PURPOSE: To control the steering angle most appropriately by providing a stopper mechanism to be brought into contact with a spring mechanism at the time of exceeding the specified steering angle so as to deform a spring elastically and increase the steering angle restoring force suddenly by this contact with the stopper mechanism, thus noticing the entering into a large steering angle position.

CONSTITUTION: The rear ends of links 5 forming a part of a spring mechanism are rotatably connected at brackets 4 provided on both sides of the upper bearing 3 of the outboard motor main body 2 of an outboard motor 1 with a large steering angle mechanism by pins 6, and the front end parts of these links 5, 5 are connected by a tension coil spring 7 with tensile strength. A stopper mechanism 10 is provided on the upper face center line 9 of a swivel bracket 8. When the steering angle θ enters the large steering angle zone of 30-60°, the links 5 are brought into contact with the stopper mechanism 10, so that steering angle restoring force is suddenly increased, and the entering into a large steering angle position is noticed.