A current sensor includes core components that form a magnetic circuit and form a space where to dispose a probe coil on the magnetic circuit; and a clip that press-joins the core components with each other. Since magnetic reluctance decreases at a portion where the core components are press-joined by the clip, an amount of magnetic flux of an external magnetic field passing through this portion increases, and accordingly, an amount of magnetic flux interlinked with the probe coil decreases. This improves the immunity of the current sensor to an external magnetic field.