A current sensor which can measure accurately current of a wide range, at low cost. A C-shaped shield plate is positioned around a flow direction of a current of the bus bar. When the current flows through the bus bar, magnetic flux density of a magnetic field is generated. A magneto-electronic conversion element detects the magnetic flux density of the magnetic field, and converts the magnetic flux density into an electric signal. Furthermore, the magneto-electronic conversion element is arranged near a position where the previously measured magnetic flux density of the magnetic field, which is generated when a current flows through the bus bar, is minimized between the conductor and the shield plate.