Fastener driving device

The invention relates to a fastener driving device, in particular to a nail gun which comprises a shell, a motor, a gun nozzle, a stock bin, an anvil, a driving cylinder, a first piston, a compression cylinder, a second piston, a cylinder cover assembly and the like. The cylinder cover assembly comprises a cylinder cover fixedly arranged with the driving cylinder and a valve assembly, and the valve assembly enables the gas channel to be switched between the opening position and the closing position. The gas channel comprises at least two gas inlet channels and a gas exhaust channel, the second piston acts on the valve assembly to enable the gas inlet channels to be in the open position, the gas inlet channels are in the closed position through the bias pressure element, and the number of the gas inlet channels is at least two. According to the nail gun, the second piston acts on the valve assembly to open the at least two air inlet channels to achieve nailing, the multiple air inlet channels are opened under