Abstract: In order to study the displacement, acceleration and stress response of tower structures under seismic loads，the finite element model of tower structure of the ship lift of Baihetan Hydropower Station was established by using ABAQUS finite element software. The results show that the maximum horizontal displacement of the top of the tower is 30.59 cm under single horizontal earthquakes, and that is 31.84 cm under combination of horizontal and vertical earthquakes, which were under the requirement of the standard. In order to study the influence of P-Δ effect on the column structure, we conducted a dynamic time history analysis on the column structure under horizontal and vertical earthquakes, considering geometrical nonlinearuty. The results show that after considering the P-Δ effect, the dynamic response of the structure is generally magnified, the maximum displacement, maximum acceleration and maximum stress increasing by about 10%, indicating that the P-Δ effect will weaken the seismic performance of the structure to a certain extent. Therefore, in the seismic performance study of tower structure, the P-Δ effect can not be ignored.