A battery protecting circuit is disclosed that includes a negative voltage terminal voltage detecting circuit that detects when a voltage of a negative voltage terminal decreases to less than a predetermined voltage; an abnormality detecting circuit that detects an abnormality in charge/discharge conditions of a battery; a switch that is connected between the battery and the negative voltage terminal, the switch being turned off when the negative voltage terminal voltage detecting circuit detects that the voltage of the negative voltage terminal has decreased to less than the predetermined voltage and when the abnormality detecting circuit detects the abnormality in the charge/discharge conditions of the battery; a delay time reducing circuit that reduces a time period from a time the abnormality in the charge/discharge conditions of the battery is detected to a time the switch is turned off when the voltage of the negative voltage terminal decreases to less than the predetermined voltage; and an output invalidating circuit that invalidates an output of the negative voltage terminal voltage detecting circuit.