Abstract: A jitter measurement device for reproducing a signal from an optical disc, which has simple circuit configuration and can effectively measure the jitter component. A matrix circuit 4 supplies the RF signals to the analog/digital converting circuit 6. Second, the computer 8 computes the slice level from the digitized data of the RF signals. Computer 8 computes the time point at which the RF signals become the indicated slice level, by interpolating, based on the digital data at the sampling point in the neighborhood of the said slice level, and the sampling frequency of the analog/digital converting circuit 6. A computer 8 computes each time breadth between the time points at which the RF signals become the slice level, then computes the jitter component of the reproduced signal, based on the each time breadth.