Abstract: Abstract：Objectives As an essential component of the ship’s power system, the shock resistance performance of steam piping directly affects the vessel’s survivability and combat capability under underwater explosion impact. Traditional finite element-based shock analysis methods fail to consider environmental factors and lack research on flange sealing performance under impact conditions. A comprehensive evaluation method for the shock resistance performance of ship steam piping, based on multi-physics coupling, is proposed. Methods The analysis was conducted on a ship steam piping system, where a "temperature-pressure-impact" multi-physics coupled finite element model was developed. Shock resistance calculations and experimental validations were carried out under various conditions, including temperature, shock amplitude, and bolt preload. The general response patterns were compared and analyzed. Structural strength and dynamic sealing performance of the steam piping under shock were comprehensively assessed based on the calculated stress and gasket pressure time-domain data. Results The results show that the model's acceleration and bolt preload errors are both below 10%, meeting engineering evaluation requirements. The method successfully predicted that under extreme shock conditions, the maximum stress at the flange transition of short piping components exceeded the material yield strength, identifying a weak point in shock resistance. Additionally, the minimum contact pressure of the gasket at the vertical connection flange (6.3 MPa) was lower than the leakage critical pressure (8.92 MPa), indicating a short-term leakage risk. Conclusions The proposed comprehensive evaluation method provides a reference for optimizing weak points in the shock resistance design of ship steam piping and enhancing sealing reliability.