The subway stray current has always been a problem due to the weak and intermittent characteristics. Analyzing and studying various characteristics of stray current signals requires a large number of stray current data. However, there is a phenomenon in the conventional stray current signal acquisition system, which features low sampling rate, slow transmission rate and simple function. This paper proposes that using FPGA part of Zynq can develop a set of multi-resolution acquisition system, which can monitor the stray current signal at low reso- lution and analyze the characteristics of the signal at high resolution. The front-end acquisition was carried out by XADC IP. Then, by using Multi-channels PreProcess IP and Single-channel PreProcess IP, this paper com- pleted the function of multi-channel signals calibration and data protocol conversion. Finally, by employing a group decimation IP, it sorted out the multi-resolution acquisition. The research results show that the multi-res- olution acquisition system on Zynq not only provides a data source for further analysis about the characteristics of stray current signal, but also can effectively monitor the signal in real time. At the same time, Zynq is helpful to solve the high-speed real-time data transmission and storage problems.