An offset corrector of an information readout apparatus receives a digital signal DRF output from an A/D converter, and performs offset correction. The offset corrector is capable of switching between a level-correction operation that corrects the offset so that the DC level of the shortest period signal included in the readout signal assumes a zero amplitude reference and a HPF operation that matches the level of the readout signal with the zero amplitude reference. The offset corrector corrects the offset in the level correction operation during a normal reproduction, and switches to the HPF operation for offset correction when a defect judgment unit detects a defective area. The information readout apparatus is stable and has a superior performance without a symmetry deviation if there occurs a waveform fluctuation caused by a defect etc.