A semiconductor memory apparatus includes a buffer control unit configured to deactivate a buffer control signal in response to an auto-refresh start pulse, and activate the buffer control signal in response to an auto-refresh end pulse, a command buffer configured to buffer an external command and output an internal command when the buffer control signal is activated, an address buffer configured to buffer an external address and output an internal address when the buffer control signal is activated, and a clock buffer configured to buffer an external clock and output an internal clock when the buffer control signal is activated.