An outboard motor (100, 200, 300) comprising: an engine including a crankshaft and configured to start when the crankshaft is rotated at a cranking rotation speed or higher, the cranking rotation speed being the lower limit of the rotation speed of the crankshaft at which initial explosion of the engine is possible; a rope reel around which a rope is wound and connected to the crankshaft; a rotary electric machine connected to the crankshaft; and a rotary electric machine controller (40, 240, 340) configured or programmed to control the rotary electric machine; wherein the rotary electric machine controller (40, 240, 340) is configured or programmed to, in a state where the crankshaft is rotated at a rotation speed within a cranking rotation speed range (Rc) including the cranking rotation speed due to rotation of the rope reel, perform assist control of assisting rotation of the crankshaft by the rotary electric machine, characterized in that the rotary electric machine controller (40, 240, 340) is further configured or programmed to, in a state where the crankshaft is rotated at a rotation speed within the cranking rotation speed range (Rc) including the cranking rotation speed due to rotation of the rope reel, perform power running rotation speed range expansion control of expanding a power running rotation speed range (Rd) of the rotary electric machine which is a range of the rotation speed of the crankshaft within which electric power is supplied from a battery to the rotary electric machine so that an upper limit value of the power running rotation speed range (Rd) is greater than the upper limit value (N1b) of the cranking rotation speed range (Rc). an engine including a crankshaft and configured to start when the crankshaft is rotated at a cranking rotation speed or higher, the cranking rotation speed being the lower limit of the rotation speed of the crankshaft at which initial explosion of the engine is possible; a rope reel around which a rope is wound and connected to the crankshaft; a rotary electric machine connected to the crankshaft; and a rotary electric machine controller (40, 240, 340) configured or programmed to control the rotary electric machine; wherein the rotary electric machine controller (40, 240, 340) is configured or programmed to, in a state where the crankshaft is rotated at a rotation speed within a cranking rotation speed range (Rc) including the cranking rotation speed due to rotation of the rope reel, perform assist control of assisting rotation of the crankshaft by the rotary electric machine, characterized in that the rotary electric machine controller (40, 240, 340) is further configured or programmed to, in a state where the crankshaft is rotated at a rotation speed within the cranking rotation speed range (Rc) including the cranking rotation speed due to rotation of the rope reel, perform power running rotation speed range expansion control of expanding a power running rotation speed range (Rd) of the rotary electric machine which is a range of the rotation speed of the crankshaft within which electric power is supplied from a battery to the rotary electric machine so that an upper limit value of the power running rotation speed range (Rd) is greater than the upper limit value (N1b) of the cranking rotation speed range (Rc).