A semiconductor memory device includes an I/O circuit suitable for inputting and outputting data signals, and a control logic suitable for controlling the I/O circuit. The control logic includes a flip-flop suitable for operating in response to a dock signal, which is irrelevant to the data signals, and feed a first output signal back, a first pulse generation circuit suitable for generating a data output control pulse in response to a second output signal of the flip-flop which is an inverted signal of the first output signal, and a second circuit suitable for generating a strobe signal in response to the second output signal.