Thermal shock experiment could test the effect of extreme temperature environment on the structure of SRM.By using thermal-structure interaction method of three-dimension finite element software， change of temperature， stress and strain of a nozzle closure of SRM subjected to thermal shock experiment was obtained. The results show that there exists temperature difference up to 46 ℃ during the temperature shock experiment； there exists differential temperature stress， too； and the stress reaches the largest of 18.13 MPa at the interface of Al alloy support element/EP sealing element at low temperature of -50 ℃， where is the site the nozzle closure breaks first. EP sealing element is the weakest part， and the internal stress in EP with adhesion structure of nozzle closure is 11.6 MPa， while that with separation structure of nozzle closure is 9.1 MPa. The influence factors of the structural integrity of the nozzle closure subjected to temperature load are obtained， which show that the selection of sealing material with low modulus and moderate coefficient of linear expansion， the choice of molding technology at room-temperature， and the separation of the interface of support element/sealing element reduces the internal stress at the interface of support element/sealing element effectively cause by thermal shock experiment. The results from thermal shock experiment for SRM with GFM/EP/Al alloy nozzle meet that of predicted.