Abstract: In order to discuss the influence of rigid pile composite foundation on soil pressure of adjacent retaining structure, a reasonable calculation method of soil pressure of retaining structure under this complex working condition is found.Based on the load transfer mechanism of rigid pile composite foundation,combined with Mindlin solution, Boussinesq solution and stress superposition principle, the simplified elastic solution of additional earth pressure of adjacent retaining structure of composite foundation load transfer effect was analyzed, and the calculation method of earth pressure of adjacent retaining structure of rigid pile composite foundation was determined.The calculation results are compared with the model test results.The results show that the load transfer mechanism of rigid pile composite foundation can be well considered by subdivision and subregion calculation of the influence of composite foundation on the soil pressure of adjacent retaining structures, and the additional soil pressure and soil pressure calculated by this method are in good agreement with the model test results, and are safe.