To provide a power steering device for a boat with an outboard motor which helps
to realize easy drive with small steering force without taking waterproofness into
consideration. A gear device (4) is provided for driving a link mechanism
for turning and steering an outboard motor main body at the rear of the boat body
through a cable by a steering wheel (2). A steering torque input to the
gear device (4) by the steering wheel (2) is detected by a torque
sensor (35) to assist-drive the gear device 4 in the steering direction
by an electric motor (27), a helical pinion (25), and a helical wheel (26).
