To provide a digital demodulator which includes performance applicable to multi-value QAM and is advantageous in power consumption, circuit scale, price and the like even for a high-speed signal, a symbol rate of which is several dozens of 10MBaud or more.

There are provided a quadrature demodulator which includes two A/D converters and outputs an in-phase signal and a quadrature signal at the same timing; first and second waveform shaping filters (output phases of which are different by T/4) for inputting the in-phase signal outputted from the quadrature demodulator; a delay circuit for delaying the quadrature signal outputted from the quadrature demodulator for one-sample time; third and fourth waveform shaping filters (output phases of which are different by T/4) for inputting an output of the delay circuit and the quadrature signal outputted from the quadrature demodulator; a timing error detection circuit for outputting a timing error signal from outputs of the waveform shaping filters; and a timing correction circuit for outputting timing-corrected in-phase and quadrature signals from the outputs of the waveform shaping filters.