The design method of composite pile foundation is introduced. Progress of total settlement of composite pile foundation is analyzed; and the method of settlement calculation is presented. The ground settlement due to the load shared by pile group is calculated with layerwise summation method based on Geddes stress method; and the ground settlement duo to the load shared by soils under pile cap is calculated with layerwise summation method based on Boussinesq’s deformation formula; the summation of two settlement above equals the total settlement of composite pile foundation. The design and settlement calculation methods have been applied to certain building with composite pile foundation; the results show that the pile number is decreased about 1/3

and saved cost 35%

while the total settlement increased a little.