A semiconductor memory device of a DDR configuration improved in glitch immunity and the convenience of use is to be provided. It is a dynamic type RAM the operation of whose internal circuit is controlled in synchronism with a clock signal; an input circuit is provided in which a second clock signal inputted when in write operation is used to take in a plurality of write data serially inputted in response to that signal into a plurality of first latch circuits, and said first clock signal is used to take the write data taken into the first latch circuits into the second latch circuit to convey them to an input/output data bus; a logic circuit is provided to mask, in accordance with the logic of the first clock signal and the second clock signal, any noise arising at the end of the second clock signal, and a third clock signal is generated and supplied to the first latch circuits which output the write data to at least the input of the second latch circuits.