[en] For development of analysis method for prestressed concrete reactor containment structures subjected to ultimate pressure, the behaviors and failure modes of the containment structures under internal pressures are analyzed. Then techniques on constitutive modeling of materials and structural modeling for the prestressed concrete containment structures are studied. Based on analyzed nonlinear behavior of the containment structures under internal pressures, finite element modeling and analyses are performed for a quarter model with axi-symmetric character and for 3D full model. From the analysis results, problems and supplementations of analysis methods for prediction of ultimate pressure capacity of the concrete reactor containment structures are derived