To provide an outboard motor capable of cooling an engine and a transmission.

The outboard motor 1 includes the transmission 21 for transmitting the power of the engine 2 to a propeller 3, a casing 6 storing the transmission 21, an engine cooling mechanism 29 for cooling the engine 2, and a transmission cooling mechanism 30 for cooling the transmission 21. The engine cooling mechanism 29 takes in water around the casing 6 by a pump 32, and the taken water is supplied to the engine 2 through an engine cooling water flow channel including a tube 34 and a second flow path 36. The transmission cooling mechanism 30 includes a water jacket 40 provided adjacently to the transmission 21, a water intake port 39 formed at a predetermined position of the casing 6 wherein dynamic pressure is acted by a water flow accompanied with traveling of a ship, and a third flow path 41 connecting the water intake port 39 and the water jacket 40 and independently provided from the engine cooling water flow channel.