Provided is a differential voltage measurement device with enhanced measurement accuracy. A differential amplifying unit outputs a voltage corresponding to a difference voltage between a voltage held by the first capacitor and a voltage held by the second capacitor. The μCOM connects a battery cell to both ends of the first capacitor, and connects the cell battery to both ends of the second after the first capacitor holds the voltage across the cell battery. SW disconnects the electrical connection between the first capacitor and the negative electrode of and the negative electrode of the cell battery. μCOM, after the first capacitor holds the voltage across the cell battery, turns off the SW.