The input nodes and output nodes of a plurality of storing circuits for storing plural-bit data are connected to one another to constitute a shift register. Each of the plurality of storing circuits includes a selection circuit for selecting 1-bit data from the plural-bit data according to a selection signal, a first latch circuit for latching the 1-bit data selected by the selection circuit in synchronism with a first clock signal, and a number of second latch circuits, which number corresponds to the number of bits of input data, for latching an output of the first latch circuit in synchronism with a plurality of second clock signals having phases different from that of the first clock signal. Data sequentially selected by the selection circuit is latched into the first latch circuit and then sequentially latched into the second latch circuit in a time-sharing fashion.