Hemispherical resonator gyro has the advantages of simple structure，radiation and shock resistance，long life and high reliability，among which signal drive and readout circuit is the key to obtain high precision gyro signal. The unit circuits that affect the performance index of the gyroscope，such as signal readout circuit，excitation circuit and power supply circuit，are studied and optimized. Based on weak signal processing and filtering technology，the method to improve the detection voltage stability is studied. Tina-TI software is used to simulate the performance of the designed circuit，and the overall circuit design is realized with a gain of 40 dB and noise of 4.81 μV/ Hz. A gyroscope prototype is built to test the readout circuit. According to the experimental results，the evolution trend of the output signal under the action of different superimposed excitation signals of HRG is given. The results show that the amplitude of the output signal increases with the increase of DC and AC voltage. When the voltage of excitation signal is constant，the frequency change of AC signal will also affect the amplitude of the output signal of hemispherical resonant gyro. Therefore，the study of the influence of the excitation signal of the hemispherical resonator gyro on the output signal provides the direction for the design of the driving circuit of the hemispherical resonator gyro.