Sulfurized Polyacrylonitrile (S-PAN) has garnered extensive attention as cathode materials for Li-S batteries in recent years because of its advantages such as high sulfur utilization efficiency, high Coulombic efficiency and low self-discharge rate. However, it is difficult to effectively balance the conflict between a high S loading ( > 45 wt%) and cycling stability for S-PAN. In this work, we employed an in situ wrapping method to improve the cycling performance of high-S-content S-PAN. Compared with the unwrapped S-PAN, the capacity retention ratio of the wrapped S-PAN cathode increased from 38% to 62% after 100 cycles at 0.25C. The analyzed results suggested that the wrapping layer on the high-S-content S-PAN may compose a mixture of sulfide, inorganic LiBxOy and some organic compounds.