A magnetic detector, wherein the magnetic/electric conversion element is constituted by at least six segments symmetrically arranged in a direction in which the magnetic moving body rotates maintaining a predetermined pitch with respect to the center line of the magnet, first and second bridge circuits are constituted so as to produce outputs accompanying the rotation of the magnetic moving body, and a third bridge circuit is constituted so as to produce an output accompanying the rotation of the magnetic moving body, and wherein a comparison level of a comparator circuit that shapes the waveform of a differential output signal of the first and second bridge circuits is adjusted relying upon an output signal of the third bridge circuit.