A non-volatile memory device is provided. The non-volatile memory device includes a clock pin, a clock signal being received from a controller through the clock pin; a first input/output pin; a second input/output pin, data being received from the controller in synchronization with the clock signal through the second input/output pin; a command/address buffer configured to operate at a first operating speed and buffer a command and an address received through the first input/output pin in synchronization with the clock signal; a memory cell array including a plurality of memory cells; and a control logic configured to control operations with respect to the plurality of memory cells, based on the command and the address buffered in the command/address buffer.