A series of finite element method (FEM) analysis were carried out to study the seismic response of the nuclear low pressure cylinder and condenser, based on the code for seismic design of building. Seismic response characteristics of the nuclear low pressure cylinder and condenser were obtained through the seismic time history analysis and spectrum analysis. The results show that the seismic response of the nuclear low pressure cylinder and condenser presents some vibration model features of plate structures, and has a better aseismic performance than general building.