Abstract: Based on a mass of experiments, a brief analysis is carried out to investigate the engineering properties of polypropylene fiber reinforced raw soil, reinforced lime soil and reinforced cement soil. The strength behavior and mechanism of polypropylene fiber reinforced soil are illustrated. It is found that the polypropylene fiber reinforcement effectively can enhance the strength and stability of soil, and makes the soil brittle failure into ductile one. Therefore, the polypropylene fiber as a better material of reinforced earth has very wide applications in the geotechnical field.