There is provided a thin film tri-gate fluxgate for detecting a component of a magnetic field in directions of three axes, the thin film tri-gate fluxgate comprising: two first thin film fluxgates of a bar-type disposed on a plane for detecting horizontal components of the magnetic field in direction of dual axis; and a plurality of second thin film fluxgates for detecting a vertical component of the magnetic field, wherein each of the first thin film fluxgates and the plurality of the second thin film fluxgates comprises a drive coil for applying a power, a pickup coil for detecting a voltage and, a magnetic thin film, and wherein the plurality of the second thin film fluxgates are substantially perpendicular to each of the first thin film fluxgates wherein a length of the magnetic thin film of each of the plurality of the second thin film fluxgates is shorter than that of each of the two first thin film fluxgates, and wherein two end portions of each of the plurality of the second thin film fluxgates is wider than a center portion thereof.