Abstract: EPS beads mixed lightweight soil is a lightweight soil with perfect mechnical properties. It can effectively improve the roadbed stability and reduce the settlement of roadbed. The strength under cyclic loading is less than that under static loading, so the static strength is dangerous to the design parameters for subgrade. Laboratory tests on the mechanical properties of EPS beads mixed lightweight soil under cyclic loading are conducted. The results show that there are two typical types of stress-strain relationships,which are failure type and stability type, and 0.75 is proposed as the critical load rate. Meanwhile the strength under cyclic loading is proposed as 75% of the unconfined compressive strength. The failure strain is greater than that in the case of loading only one time, while decreases with the load rate. The rebound curve and re-compression curve are of the same slope, which remain basically unchanged with the increase of cyclic times.