Aiming at the problems of low precision and big fluctuation of voltage and current data acquisition in the process of inertial navigation system, in this paper, an anti-noise high precision data acquisition, and processing system has been designed and implemented based on AD7176-2 and STM32. The acquisition system mainly includes signal isolation circuit, external excitation circuit, front analog amplifier circuit, AD conversion circuit, and software platform. The 24-bit high precision AD converter with an external voltage reference source converts the analog voltage and current signal output by the current source to the digital signal. The digital signal is filtered by the internal filter of ADC and the anti-pulse interference digital filter, then it is processed and transmitted to the host computer through the embedded microprocessor. After a series of experiments and tests, the detailed experimental data and results show that the data acquisition system can operate continuously and stably with very low noise,high precision and large dynamic range.