As an important inertial navigation sensor, resonant fiber optic gyro (RFOG) has become a research hotspot in recent years due to its advantages of light weight and high stability. The optical effects in the fiber ring resonator(FRR), such as scattering effects, polarization mode crosstalk, etc., are the bottleneck restricting the development of RFOG, and they are also the key problems that researchers are trying to solve. Aiming at the problem of polarization noise, this paper conducts in-depth theoretical and experimental research on polarization stability using spun fiber resonator for the first time. Compared with a common polarization-maintaining fiber (PMF) resonator of the same length, the results show that the RFOG using the spun fiber resonator has improved temperature stability compared to the conventional resonator structure. This research provides a new idea for the polarization noise suppression method of RFOG, and lays an important foundation for the practical application of spun fiber in RFOG.