An outboard motor engine drives an output shaft which drives a propeller shaft. The output shaft has a drive gear that engages driven gears of the propeller shaft within an oil bath for holding a lubricant for soaking the drive and driven gears. The outboard motor has an oil pump, a suction passage, and a return passage. The oil bath communicates with a suction portion of the oil pump through the suction passage, while a discharge portion of the oil pump communicates with the oil bath through a return passage. An opening of the suction passage is exposed to the oil bath and is also positioned below the drive gear.