Abstract: Based on the API code, the double-parameter modified method and the revised computational formula for lateral dynamic p–y curves of pile foundation in liquefiable soil layers are presented by using pile-soil shaking table tests, and as a result, the unacceptable problem of the current coefficients for calculating the dynamic p-y curves by the API code in engineering practice can be solved. Using four different densities of liquefiable sand layers in the shaking table tests by incident sinusoidal waves and taking the sand density as a major factor, the initial modulus and ultimate soil resistance parameters in the API code are modified. Using shaking table tests on pile-soil liquefaction interaction by incident irregular seismic waves the modified method and the revised computational formula are verified. It is indicated that the modified method and the revised formula are agreeable with the test results. The expression of the revised formula is as simple as that in the API code and is convenient for practical engineering application.