In a power switching apparatus of an outboard engine wherein a shifter dog is moved by a shift cam to engage with a forward gear or a reverse gear for rotating a propeller of a boat in the forward or rearward direction, there is provided a clutch mechanism interposed between a shift rod connected to the shift cam and a clutch rod. The clutch mechanism comprises a clutch housing, the diameter of the intermediate portion of an inner opening of the housing being reduced. The housing is formed with large diameter openings at its upper and lower portions. The clutch mechanism further comprises spring housings respectively fitted in the large diameter portions, a plunger with its large diameter portions at the upper and lower ends fitted in the spring housings respectively, shift springs interposed between the inner bottoms of respective spring openings and the large diameter portions of the plunger, locking balls for locking and unlocking the spring housings with the plunger, and detent mechanism for positioning the spring housings in the neutral position whereby the shift cam is moved through the shift spring when the shifter dog engages with the gears, whereas the shift cam is moved integrally with the clutch rod through the spring housings and the plunger when the shifter dog disengages from the gears.