An offset adjusting circuit for an optical disc comprises an offset-adjustment differential operational amplifier having an input terminal to which an output signal of an optical pickup is input and the other input terminal to which a control voltage is applied, an A/D converter that outputs a digital signal based on an output signal of the offset-adjustment differential operational amplifier, and a control voltage adjuster that varies the control voltage applied to the offset-adjustment differential operational amplifier based on the digital signal so as to remove an offset.