Abstract: In this paper, the seismic performance analysis for bent structure of iodine absorber LSJH-31-1 was carried out under the combined loads, including dead weight, earthquake loads, internal pressure by using spectrum analysis method in ANSYS. The stress qualification was also carried out based on EJ/T 1116—2000 code on mechanical equipment design of ventilation, air-conditioning and gas treatment systems in nuclear facilities. The results show that the stress of bent structure meets the seismic requirements for equipment, and the deformation of structure is within the allowable limits.