The combined treatment of enzyme induced calcium carbonate precipitation (EICP) and xanthan gum can improve the mechanical properties of seasonally frozen sandy soil, providing a new approach for its development and utilization. By conducting freeze-thaw cycle tests, UCS tests, direct shear tests, SEM and XRD tests indoors, the blending ratio process of xanthan gum EICP improved sandy soil was optimized based on response surface methodology, and the macroscopic mechanics and microscopic structure of the improved sandy soil were studied under freeze-thaw cycles. The research results indicate that the mechanical properties of the modified loess soil samples with xanthan gum EICP have been significantly improved. Based on the changes in various strength parameters of the modified loess soil samples with EICP xanthan gum, the optimal strength parameters were obtained when the curing period was 7 days, the xanthan gum content was 1.465%, and the volume ratio of the binder to soybean urease was 1:1. Xanthan gum EICP modified sandy soil can delay internal damage caused by freeze-thaw cycles and effectively improve shear strength. Through microstructure analysis, the failure process of EICP xanthan gum modified sandy soil samples under freeze-thaw cycles and the factors that reduce various strength parameters were elucidated.