A comparative study of a two-phase finite element structural analysis has been undertaken by members of Technical Comittee II. 1 of ISSC '94. A side structure of a middle size crude oil carrier was taken as a typical example of an orthogonally stiffened panel structure. The first phase of the analysis was the global deformation and stress analysis of the side structure while the second phase was the local stress analysis at the intersection of a transverse frame and a longitudinal stiffener. The numerical results are summarized, and investigations are made for the possible sources of the differences observed in the study.