An electric bicycle and a battery lift mechanism and a battery carrying device thereof are disclosed. The battery lift mechanism includes a bracket, a carrier for carrying a battery, an upward-force device coupling with the carrier, and a locking device selectively in an unlocked state or a locked state. The carrier is movable relative to the bracket along an up-down path; the upward-force device is capable of applying an upward force to the carrier. When the locking device is in the locked state, the locking device interferes with the battery to limit the relative movement between the battery and the bracket. When the locking device is in the unlocked state, the interference between the locking device and the battery is removed, so that the upward-force device drives the carrier carrying the battery to move upward relative to the bracket.