An exemplary electronic device includes a casing, a first switch, a second switch and a switch control unit. The second switch is connected in parallel with the first switch. The casing includes a side plate and a top plate detachably connected with a top end of the side plate. The first switch is turned on when the top plate mounted to the side plate and turned off when the top plate detached from the side plate. The switch control unit includes a sliding member mounted at the second switch. The sliding member includes a pressing plate and is moveable relative to the side plate between a first position in which the pressing plate aligned with and pressing the second switch to turn on the second switch and a second position in which the pressing plate is staggered with the second switch to turn off the second switch.