The present invention is directed to realize high-speed operation and low latency of a semiconductor storage device employing the QDR method. A memory cell array, a first buffer, a second buffer, a first circuit, a second circuit, a first DLL circuit, and a second DLL circuit are provided. The first DLL circuit generates a first internal clock signal so as to reduce a phase difference between a first clock signal fetched via the first buffer and the first internal clock signal transmitted to the first circuit. The second DLL circuit generates the second internal clock signal so as to reduce a phase difference between the second clock signal fetched via the second buffer and the second internal clock signal transmitted to the second circuit. With the configuration, input setup and hold time can be shortened, and the frequency of the clock signal can be further increased.