Provided is a current sensor including a first Hall element and a second Hall element. Provided is a current sensor including a first Hall element; a second Hall element; a primary conductor arranged in a manner to have a current under measurement flow therethrough and to apply magnetic fields under measurement caused by the current under measurement, with different polarities, to the first Hall element and the second Hall element; and a secondary conductor arranged in a manner to have a reference current flow therethrough and to apply reference magnetic fields caused by the reference current, with the same polarity, to the first Hall element and the second Hall element.