With the continuous development of underwater weapons such as torpedoes and naval mines， the survivability of ships is facing increasingly severe threats. Under underwater contact explosions， multiple damage elements， including shock waves， bubble pulsations， and secondary fragments， interact with each other， which can easily cause severe damage to hull structures. To address this， this paper first analyzes the load characteristics of underwater contact explosions and systematically reviews the spatial-temporal evolution laws of shock waves， bubble pulsations， and secondary fragments. On this basis， the protective mechanisms of ship underwater protection systems are examined from two perspectives： multi-compartment protective structures and protective schemes employing composite structures and materials. Finally， key technical challenges that urgently need to be resolved in current research are identified， with the aim of providing a useful reference for the future development of ship damage and protection technologies against underwater contact explosions.