This paper studies a circuit design of three-dimensional orientation sensor with high precision. Firstly, a circuit of one-dimensional orientation magnetic sensor is studied, the wheat-stone bridge exports difference voltage signal, which will be magnified and commutated. The reset/set coil of the magnetic sensor improves the sensitivity; the compensation coil of the magnetic sensor engenders magnetic field through the integral circuit, when the intensity of magnetic field is equal to earth magnetic fields, the output voltage of integral circuit is invariable, so the intensity of magnetic field of compensation coil can be calculated, namely the intensity of earth magnetic field. The compensation coil overcomes the temperature drifting phenomenon effectively; and the offset voltage is removed through feedback circuit. Then the three-dimensional orientation magnetic sensor is studied further. Moreover the simulation has been executed of this circuit.