The work on the second generation intact stability criterion is on trial now, and the vulnerability criterion assessment method of dead ship stability has already been confirmed. The dead ship stability is formulated to improve the safety of ship navigation at sea, compared with other failure modes in the second generation intact stability, there are some problems in the principle consistency of the dead ship stability vulnerability criteria. In order to make the criteria more scientific and early comprehensive application, the calculation principle and evaluation method of the dead ship stability vulnerability criteria are studied, the principle similarities and differences between the first and second level are analyzed, and the reasons affecting the consistency are explored through the calculation results of the sample ship. Firstly, the theory of dead ship stability assessment method is summarized, and the similarities and differences between level 1 and level 2 assessment method are analyzed, then sample ships have been calculated, including sea guard ships, patrol ships, fishery administration vessels and oil tankers. According to calculation results, the consistency between level 1 and level 2 is studied and the corresponding conclusion is obtained, which provides test data support to the completion of dead ship stability vulnerability criterion.