Abstract: In order to study the influencing factors that affect the regid column composite foundation, a self-made test device was used to carry out indoor compression tests on regid column composite foundation. Based on the main influencing factors that affect the settlement of the regid column composite foundation with different pile lengths, different pile diameters, different cushion thickness and the different number of pipes (with the same replacement rate) was numerically simulated by the finite element simulation software (Duncan-Chang model used for soil mass selection). The results show that, with the increase of pile length and pile diameter, the settlement of rigid pile composite foundation decreases, and controlling pile length has more significant effect than controlling pile diameter on the settlement of rigid pile composite foundation; and the demarcation point of the positive and negative frictional resistance of the pile is roughly in the range of 0.4~0.6 times the pile length, pile-soil stress ratio varies between 15~17. When the thickness of the cushion layer is relatively small, the effect of force adjustment between pile side friction and the pile soil is not obvious, and when the thickness of the cushion layer is relatively large, the overall settlement will increase. In the actual project, the thickness of the cushion layer should be designed reasonably. Then it is recommended to use 30~50 cm.