The law of the average settlement varying with load, the average pile-soil stress ratio and the load transfer law for the composite foundation with rammed cement-soil piles were studied experimentally. The results indicate that under the same load, the average settlement of composite foundation with geogrid is smaller than that of composite foundation without geogrid, the average pile-soil stress ratio with geogrid is larger than that without geogrid and the axial stress of pile with geogrid is greater than that without geogrid. With the same load，the axial force of the center piles is smallest and the axial force of the corner piles is biggest.