In order to ensure the clearance and uniformity of the components, the interference assembly strength of the nozzle components of the rocket engine was analyzed. Based on the background of engineering application, the process of interference mounting between nozzle body and throat liner of certain type standard test engine is simulated and analyzed. Carry out the dynamic and thermodynamic analysis of the nozzle components under the conditions of heated and unheated by finite element method. The results show that the contact stress of the assembly surface is smaller, which is more conductive to control the assembly interference and ensure the assembly quality of the nozzle assembly if the nozzle body is heated before assembling.