Biodegradable spun-bonded non-woven fabric slices of poly lactic acid (PLA)/polypropylene (PP) were prepared by melt blending. The influence of the proportion of raw materials, blending temperature, blending time and rotation speed on the mechanical properties and melt flow properties of the slices were investigated, the influence of the proportion of PLA and PP composite slices on the thermal properties and microstructure was also researched. According to the research results of optimization conditions, the biodegradable spun-bonded non-woven fabric slice of PLA/PP was prepared and its biodegradable performance was evaluated. The results showed that when (m)PLA:(m)PP was 8:2, blending temperature was 185 degrees C, blending time was 4 min and rotation speed was 50 min(-1), the melt blending condition of PLA/PP composite slices was optimal. With the increase of PP mass fraction in slices, slices of melt flow rate (MFR) and glass transition temperature (T-g) were on the decline; T-50%, T-95% and T-p were on the rise; the crystallinity of PLA/PP slices was increased; SEM results showed that the slices had "seaisland" structure. When (m)PLA: (m)PP was 8:2, microorganisms on the slices surface were second level of growth after 28 days which showed that the slices has a good biodegradable performance.