A vehicle power switching device characterized by: a power transmission unit including an input shaft adapted to be driven by a vehicle power to rotate, an output shaft aligned with and spaced apart from said input shaft, a first coupler sleeved movably on one of said input shaft and said output shaft, a differential driven by said output shaft, an axle aligned with said differential, and a second coupler sleeved movably on one of said differential and said axle and movable to interconnect said differential and said axle; and a driving unit including a controller being one of a solenoid and an electric actuator, a first transmission mechanism driven by said controller, and a second transmission mechanism driven by said first transmission mechanism, said controller being operable to activate said first transmission mechanism to thereby move said first coupler among a two-wheel drive position, a four-wheel drive position, and a differential locking position such that, when said first coupler is at the two-wheel drive position, said first coupler is sleeved on only the one of said input shaft and said output shaft, so that said input shaft is disconnected from said output shaft and said differential; when said first coupler is at the four-wheel drive position, said first coupler is sleeved on said input shaft and said output shaft to allow for co-rotation of said input shaft and said output shaft, and said differential is disconnected from said axle; and when said first coupler is moved from the four-wheel drive position to the differential locking position, said second transmission mechanism is driven by a translational movement of said first transmission mechanism to move said second coupler to interconnect said differential and said axle, so as to allow for co-rotation of said axle with said differential. a power transmission unit including an input shaft adapted to be driven by a vehicle power to rotate, an output shaft aligned with and spaced apart from said input shaft, a first coupler sleeved movably on one of said input shaft and said output shaft, a differential driven by said output shaft, an axle aligned with said differential, and a second coupler sleeved movably on one of said differential and said axle and movable to interconnect said differential and said axle; and a driving unit including a controller being one of a solenoid and an electric actuator, a first transmission mechanism driven by said controller, and a second transmission mechanism driven by said first transmission mechanism, said controller being operable to activate said first transmission mechanism to thereby move said first coupler among a two-wheel drive position, a four-wheel drive position, and a differential locking position such that, when said first coupler is at the two-wheel drive position, said first coupler is sleeved on only the one of said input shaft and said output shaft, so that said input shaft is disconnected from said output shaft and said differential; when said first coupler is at the four-wheel drive position, said first coupler is sleeved on said input shaft and said output shaft to allow for co-rotation of said input shaft and said output shaft, and said differential is disconnected from said axle; and when said first coupler is moved from the four-wheel drive position to the differential locking position, said second transmission mechanism is driven by a translational movement of said first transmission mechanism to move said second coupler to interconnect said differential and said axle, so as to allow for co-rotation of said axle with said differential.