Abstract: To improve decision-making ability of a surface vessel against a submarine, so as to decrease the counterat-tack possibility of the submarine in the process of antisubmarine warfare, the necessity of evaluation of submarine threat against surface vessel is analyzed, and the purpose and principle of the threat evaluation are discussed. An idea of de-signing a submarine threat evaluation model for surface vessels is put forward. The steps and architecture of the threat evaluation model are described in detail, and two main submodels, i.e. the attack intention inference model and the at-tack ability evaluation model, are discussed intensively. The idea may offer a reference for realizing submarine threat evaluation for surface vessels.