PROBLEM TO BE SOLVED: To provide a braking device of a portable implement, capable of accurately stopping the motion of a knife operated by inertia.SOLUTION: A core body 54 of an electromagnet 48 is disposed facing a clutch drum 44a. When an acceleration sensor 24 detects an impact, an engine 14 is urgently stopped. If the voltage of the power generated by a power generator 70 is reduced to a prescribed value, a first resetting IC of a rotational frequency detection circuit 80 is actuated, by which a brake-on signal is output from a controller (a microcomputer) 26 to an electromagnetic braking mechanism 42. The electromagnetic braking mechanism 42 includes the electromagnet 48 and a capacitor 74. The electromagnet 48 is driven with the capacitor 74 as a power supply, and the core body 54 of the electromagnet 48 is electromagnetically attracted to the clutch drum 44a.
