To study the work behavior differences of the composite foundations with stepped cross-section piles and uniform piles under cyclic load, conducted indoor contrast model tests on the composite foundations with 9 stepped cross-section piles and uniform section piles, analyzed the influence law of cyclic loading numbers on the permanent settlement and the pile-soil stress ratio of the composite foundations with stepped cross-section piles and uniform piles, and studied the strain distribution law along the piles under cyclic loading. The results show that the settlement rates of stepped cross-section piles and uniform piles are comparatively large at first, with the increment of loading times, the settlement rates decrease gradually and tend to be stable. Under the same loading conditions, the settlement of stepped cross-section piles is significantly less than that of the uniform piles, and the former tends to be stable firstly. The pile-soil stress ratio decreases with the increment of the number of loading, and the reduction magnitude is very large at first, then decreases slowly and tends to be stable. Under the same conditions, the pile-soil stress ratio of stepped cross-section piles is greater than that of uniform section piles, and the former tends to be stable firstly. For the stepped cross-section pile, the upper and lower section respectively emerge a strain peak value, and the upper pile strain peak is greater than that of the lower pile. And the uniform pile only emerges a strain peak.